pmb.flasher: fix "flasher boot" crash if cmdline is empty

Fixes #2385 (closed)

(031153) [01:01:16] (native) % fastboot boot /mnt/rootfs_fairphone-fp4/boot/boot.img
< waiting for any device >

approved this merge request

approved this merge request

Thank you very much @HenriDellal!

mentioned in commit HenriDellal/pmbootstrap@15d9516c

added 6 commits

• 7cc5d5b3...0ab75cfe - 5 commits from branch postmarketOS:master
• 15d9516c - pmb.flasher: fix "flasher boot" crash if cmdline is empty

Compare with previous version

enabled an automatic merge when all merge checks for 15d9516c pass

canceled the automatic merge

merged

That's a weird workaround imo but okay, glad it's fixed now