Makefile: Add macro to disable unsupported programmers

`mark_unsupported` disables all programmers passed as arguments and
adds them to the UNSUPPORTED_FEATURES list. It's conveniently used
with our dependency lists, e.g.

    $(call mark_unsupported,$(NEEDS_LIBUSB1) $(NEEDS_LIBFTDI))

Change-Id: I6c9b66dfa89ec3d71675576d03fcebfdea30ce7b
Signed-off-by: Nico Huber <nico.h@gmx.de>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/55873
Original-Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/71405
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
1 file changed