extmod/vfs_lfs: Fix bug when passing no args to constructor and mkfs.
extmod/vfs_lfs: Fix bug when passing no args to constructor and mkfs.

tobbad/micropython,MrSurly/micropython,kerneltask/micropython,pozetroninc/micropython,pramasoul/micropython,selste/micropython,kerneltask/micropython,MrSurly/micropython,adafruit/circuitpython,pramasoul/micropython,adafruit/circuitpython,adafruit/circuitpython,bvernoux/micropython,selste/micropython,pramasoul/micropython,henriknelson/micropython,kerneltask/micropython,trezor/micropython,MrSurly/micropython,bvernoux/micropython,trezor/micropython,trezor/micropython,kerneltask/micropython,tobbad/micropython,tobbad/micropython,trezor/micropython,henriknelson/micropython,pozetroninc/micropython,bvernoux/micropython,selste/micropython,adafruit/circuitpython,kerneltask/micropython,bvernoux/micropython,adafruit/circuitpython,MrSurly/micropython,bvernoux/micropython,pozetroninc/micropython,henriknelson/micropython,pramasoul/micropython,henriknelson/micropython,MrSurly/micropython,pozetroninc/micropython,selste/micropython,henriknelson/micropython,trezor/micropython,pramasoul/micropython,selste/micropython,adafruit/circuitpython,tobbad/micropython,pozetroninc/micropython,tobbad/micropython