Create documentation on padmelon, including how to program the SPI. Also
include an index.md pointing to the documentation, as currently there's no
maiboard documentation folder for AMD.
BUG=none.
TEST=none.
Change-Id: I1a684c1acd3fb9441df71e2bc0fffa6131148b98
Signed-off-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34493
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>