stmhal/sdcard: Allow to do unaligned read-from/write-to SD card.
stmhal/sdcard: Allow to do unaligned read-from/write-to SD card.

For example, the following code now works with a file on the SD card:

    f = open('test', 'rb') # test must be 1024 bytes or more in size
    f.seek(511)
    f.read(513)

Also works for writing.

Fixes issue #1863.

bvernoux/micropython,redbear/micropython,drrk/micropython,dmazzella/micropython,pramasoul/micropython,lowRISC/micropython,adafruit/circuitpython,adafruit/circuitpython,drrk/micropython,AriZuu/micropython,MrSurly/micropython-esp32,infinnovation/micropython,Timmenem/micropython,kerneltask/micropython,alex-march/micropython,toolmacher/micropython,blazewicz/micropython,Peetz0r/micropython-esp32,dinau/micropython,PappaPeppar/micropython,infinnovation/micropython,alex-robbins/micropython,tobbad/micropython,tobbad/micropython,hosaka/micropython,swegener/micropython,infinnovation/micropython,torwag/micropython,dmazzella/micropython,selste/micropython,tobbad/micropython,torwag/micropython,jmarcelino/pycom-micropython,turbinenreiter/micropython,dxxb/micropython,kerneltask/micropython,emfcamp/micropython,deshipu/micropython,praemdonck/micropython,tralamazza/micropython,pozetroninc/micropython,blazewicz/micropython,chrisdearman/micropython,trezor/micropython,mhoffma/micropython,lowRISC/micropython,micropython/micropython-esp32,MrSurly/micropython,SHA2017-badge/micropython-esp32,adafruit/circuitpython,tralamazza/micropython,jmarcelino/pycom-micropython,Peetz0r/micropython-esp32,TDAbboud/micropython,adafruit/micropython,henriknelson/micropython,redbear/micropython,adafruit/micropython,emfcamp/micropython,hosaka/micropython,ganshun666/micropython,dxxb/micropython,misterdanb/micropython,PappaPeppar/micropython,pfalcon/micropython,drrk/micropython,Peetz0r/micropython-esp32,pramasoul/micropython,dxxb/micropython,toolmacher/micropython,MrSurly/micropython-esp32,henriknelson/micropython,tuc-osg/micropython,Timmenem/micropython,dmazzella/micropython,hiway/micropython,matthewelse/micropython,mhoffma/micropython,misterdanb/micropython,TDAbboud/micropython,cwyark/micropython,chrisdearman/micropython,lowRISC/micropython,tobbad/micropython,cwyark/micropython,jmarcelino/pycom-micropython,trezor/micropython,praemdonck/micropython,hosaka/micropython,adafruit/circuitpython,dinau/micropython,swegener/micropython,ganshun666/micropython,micropython/micropython-esp32,mpalomer/micropython,HenrikSolver/micropython,trezor/micropython,bvernoux/micropython,SHA2017-badge/micropython-esp32,tuc-osg/micropython,mpalomer/micropython,torwag/micropython,oopy/micropython,matthewelse/micropython,redbear/micropython,jmarcelino/pycom-micropython,henriknelson/micropython,tralamazza/micropython,misterdanb/micropython,praemdonck/micropython,blazewicz/micropython,lowRISC/micropython,TDAbboud/micropython,infinnovation/micropython,adafruit/circuitpython,AriZuu/micropython,ryannathans/micropython,pramasoul/micropython,adafruit/circuitpython,ryannathans/micropython,kerneltask/micropython,pozetroninc/micropython,ryannathans/micropython,kerneltask/micropython,pozetroninc/micropython,dinau/micropython,torwag/micropython,mpalomer/micropython,dxxb/micropython,hosaka/micropython,TDAbboud/micropython,swegener/micropython,MrSurly/micropython-esp32,HenrikSolver/micropython,dinau/micropython,turbinenreiter/micropython,swegener/micropython,mpalomer/micropython,Timmenem/micropython,adafruit/micropython,adafruit/micropython,HenrikSolver/micropython,chrisdearman/micropython,hiway/micropython,pfalcon/micropython,alex-robbins/micropython,HenrikSolver/micropython,emfcamp/micropython,blazewicz/micropython,bvernoux/micropython,infinnovation/micropython,Peetz0r/micropython-esp32,AriZuu/micropython,MrSurly/micropython,cwyark/micropython,toolmacher/micropython,puuu/micropython,bvernoux/micropython,puuu/micropython,ryannathans/micropython,tuc-osg/micropython,hiway/micropython,micropython/micropython-esp32,turbinenreiter/micropython,matthewelse/micropython,dxxb/micropython,PappaPeppar/micropython,ganshun666/micropython,mhoffma/micropython,chrisdearman/micropython,MrSurly/micropython,henriknelson/micropython,drrk/micropython,trezor/micropython,tuc-osg/micropython,kerneltask/micropython,selste/micropython,matthewelse/micropython,dinau/micropython,matthewelse/micropython,pfalcon/micropython,adafruit/micropython,SHA2017-badge/micropython-esp32,praemdonck/micropython,mpalomer/micropython,misterdanb/micropython,alex-robbins/micropython,mhoffma/micropython,HenrikSolver/micropython,deshipu/micropython,MrSurly/micropython-esp32,alex-march/micropython,Timmenem/micropython,alex-march/micropython,puuu/micropython,AriZuu/micropython,bvernoux/micropython,TDAbboud/micropython,PappaPeppar/micropython,deshipu/micropython,selste/micropython,deshipu/micropython,micropython/micropython-esp32,alex-robbins/micropython,redbear/micropython,Peetz0r/micropython-esp32,alex-march/micropython,torwag/micropython,dmazzella/micropython,turbinenreiter/micropython,hosaka/micropython,pozetroninc/micropython,pfalcon/micropython,pozetroninc/micropython,lowRISC/micropython,oopy/micropython,chrisdearman/micropython,turbinenreiter/micropython,MrSurly/micropython-esp32,drrk/micropython,ryannathans/micropython,Timmenem/micropython,ganshun666/micropython,selste/micropython,puuu/micropython,pramasoul/micropython,pramasoul/micropython,oopy/micropython,redbear/micropython,micropython/micropython-esp32,misterdanb/micropython,mhoffma/micropython,ganshun666/micropython,SHA2017-badge/micropython-esp32,swegener/micropython,hiway/micropython,selste/micropython,cwyark/micropython,oopy/micropython,MrSurly/micropython,oopy/micropython,alex-march/micropython,tralamazza/micropython,tobbad/micropython,AriZuu/micropython,MrSurly/micropython,deshipu/micropython,emfcamp/micropython,SHA2017-badge/micropython-esp32,emfcamp/micropython,toolmacher/micropython,alex-robbins/micropython,praemdonck/micropython,toolmacher/micropython,trezor/micropython,cwyark/micropython,jmarcelino/pycom-micropython,puuu/micropython,henriknelson/micropython,matthewelse/micropython,blazewicz/micropython,hiway/micropython,pfalcon/micropython,PappaPeppar/micropython,tuc-osg/micropython