amd/common/spi: Update flash driver usage

Fix how the SPI driver is accessed in spi_SaveS3info.  This code has
been unused to date.

Change-Id: Ie2b97c13079fd049f6e02f3ff8fa630ed880343f
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/22406
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed