Enable BLE where we can. Switch 4MB, non-USB board default partitioning
over to a single 2MB firmware bank. Old boards override this setting to
keep the same behavior.
This also adds alpha support for the ESP32-C2 (aka ESP8684).
Fixes#5926 and fixes#7170
This can be tested using ports/minimal and qemu:
make CC=mips-linux-gnu-gcc-8
Then run with qemu-mips:
stty raw opost -echo;
QEMU_LD_PREFIX=/usr/mips-linux-gnu/ qemu-mips build/firmware.elf;
sleep 1; reset
Signed-off-by: Jan Willeke <willeke@smartmote.de>