On single core Pi versions without WiFi/Bluetooth hardware (Pi Zero,
B2, B+, …) epd-fuse initialisation can fail due to a race condition
between serial port and epd-fuse init. By waiting till after
/dev/serial1 init (which times out on these Pi versions) we make sure
epd-fuse init succeeds.
See commit comments. Kept the timeout on the default 90 sec. Shorter time-outs make the boot fail on Pi Zero (no network). More robust to keep the default.
On single core Pi versions without WiFi/Bluetooth hardware (Pi Zero, B2, B+, …) epd-fuse initialisation can fail due to a race condition between serial port and epd-fuse init. By waiting till after /dev/serial1 init (which times out on these Pi versions) we make sure epd-fuse init succeeds.