soc/amd/stoneyridge: Normalize GPIO init

This makes the flow for GPIO initialization more closely follow that
what is performed for other boards so that it's easier to read the flow
(and stops relying on BS_WRITE_TABLES).

TEST=Built and booted grunt, built gardenia.

Change-Id: Ic97db96581a69798b193a6bdeb93644f6a74fc9d
Signed-off-by: Justin TerAvest <>
Reviewed-by: Aaron Durbin <>
Tested-by: build bot (Jenkins) <>
13 files changed