x86: Set BOOT_MEDIA_SPI_BUS

BOOT_MEDIA_SPI_BUS is a Kconfig variable used on some ARM-based
platforms to set up CBFS media. It turns out it can also be helpful
for setting up the eventlog which is intended to reside on the same
SPI flash as CBFS. Setting it for x86 will allow us to remove an
assumption about which SPI bus is used for this flash device.

Long term this can go away as we come up with a better abstraction
for the eventlog's backing store. This is only intended to help us
get from here to there.

BUG=none
BRANCH=none
TEST=built and booted on Link
Signed-off-by: David Hendricks <dhendrix@chromium.org>

Original-Change-Id: I1d84dc28592fbece33a70167be59e83bca9cd7bc
Original-Reviewed-on: https://chromium-review.googlesource.com/191202
Original-Tested-by: David Hendricks <dhendrix@chromium.org>
Original-Reviewed-by: Gabe Black <gabeblack@chromium.org>
Original-Commit-Queue: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 200aa7c5b1b1f4c74412893cf7231a12e2702463)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: If988bcff5244ec6a82580203471b25fac49c45ef
Reviewed-on: http://review.coreboot.org/7752
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
1 file changed