unix/Makefile: Disable assertions in the standard unix executable.
unix/Makefile: Disable assertions in the standard unix executable.

Reasons to disable:
- the code is relatively robust so doesn't need full checking in the
  main executable, and the coverage build is used for full testing
  with assertions still enabled;
- reduces code size noticeably, by 27k for x86-64 and 20k for x86;
- allows to more easily track changes in code size, since assertions
  can skew things.

chrisdearman/micropython,ryannathans/micropython,blazewicz/micropython,tralamazza/micropython,adafruit/micropython,chrisdearman/micropython,tobbad/micropython,tobbad/micropython,micropython/micropython-esp32,HenrikSolver/micropython,dmazzella/micropython,selste/micropython,MrSurly/micropython,tobbad/micropython,SHA2017-badge/micropython-esp32,pfalcon/micropython,swegener/micropython,adafruit/circuitpython,PappaPeppar/micropython,bvernoux/micropython,torwag/micropython,kerneltask/micropython,chrisdearman/micropython,trezor/micropython,blazewicz/micropython,alex-robbins/micropython,adafruit/circuitpython,tobbad/micropython,pfalcon/micropython,AriZuu/micropython,MrSurly/micropython,adafruit/circuitpython,oopy/micropython,dmazzella/micropython,AriZuu/micropython,adafruit/micropython,pozetroninc/micropython,infinnovation/micropython,micropython/micropython-esp32,torwag/micropython,pozetroninc/micropython,Timmenem/micropython,deshipu/micropython,pozetroninc/micropython,kerneltask/micropython,Timmenem/micropython,ryannathans/micropython,PappaPeppar/micropython,oopy/micropython,bvernoux/micropython,adafruit/circuitpython,SHA2017-badge/micropython-esp32,blazewicz/micropython,oopy/micropython,PappaPeppar/micropython,pramasoul/micropython,pramasoul/micropython,TDAbboud/micropython,TDAbboud/micropython,Timmenem/micropython,pfalcon/micropython,micropython/micropython-esp32,deshipu/micropython,henriknelson/micropython,lowRISC/micropython,selste/micropython,HenrikSolver/micropython,Timmenem/micropython,Timmenem/micropython,swegener/micropython,alex-robbins/micropython,HenrikSolver/micropython,AriZuu/micropython,TDAbboud/micropython,henriknelson/micropython,torwag/micropython,lowRISC/micropython,TDAbboud/micropython,SHA2017-badge/micropython-esp32,henriknelson/micropython,selste/micropython,adafruit/circuitpython,SHA2017-badge/micropython-esp32,infinnovation/micropython,pramasoul/micropython,blazewicz/micropython,dmazzella/micropython,trezor/micropython,MrSurly/micropython-esp32,TDAbboud/micropython,dmazzella/micropython,MrSurly/micropython-esp32,lowRISC/micropython,deshipu/micropython,selste/micropython,PappaPeppar/micropython,swegener/micropython,pfalcon/micropython,pozetroninc/micropython,deshipu/micropython,ryannathans/micropython,lowRISC/micropython,micropython/micropython-esp32,swegener/micropython,ryannathans/micropython,ryannathans/micropython,pramasoul/micropython,infinnovation/micropython,MrSurly/micropython-esp32,MrSurly/micropython-esp32,swegener/micropython,chrisdearman/micropython,alex-robbins/micropython,infinnovation/micropython,pramasoul/micropython,deshipu/micropython,MrSurly/micropython,pfalcon/micropython,alex-robbins/micropython,AriZuu/micropython,MrSurly/micropython,adafruit/circuitpython,adafruit/micropython,kerneltask/micropython,torwag/micropython,bvernoux/micropython,trezor/micropython,trezor/micropython,HenrikSolver/micropython,blazewicz/micropython,MrSurly/micropython,tobbad/micropython,oopy/micropython,henriknelson/micropython,SHA2017-badge/micropython-esp32,infinnovation/micropython,MrSurly/micropython-esp32,alex-robbins/micropython,pozetroninc/micropython,micropython/micropython-esp32,adafruit/micropython,selste/micropython,kerneltask/micropython,adafruit/micropython,kerneltask/micropython,AriZuu/micropython,tralamazza/micropython,tralamazza/micropython,henriknelson/micropython,lowRISC/micropython,trezor/micropython,torwag/micropython,oopy/micropython,PappaPeppar/micropython,bvernoux/micropython,bvernoux/micropython,HenrikSolver/micropython,tralamazza/micropython,chrisdearman/micropython