amd_imc/sb600spi: Move handle_imc() into amd_imc.c

Move handle_imc() to make it easier to share it with other drivers.

Change-Id: I72dff5feda199e1d258c067e230abdf33c451249
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/72575
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
3 files changed