Stoney Ridge Platforms: Make AGESA callout tables common

There was no reason to have the AGESA callout tables in each mainboard,
so move them to soc/amd/common.

Move chip specific functions into the stoneyridge directory:
- agesa_fch_initreset
- agesa_fch_initenv
- agesa_ReadSpd

Combine agesa_ReadSpd and agesa_ReadSpd_from_cbfs, and figure out which
to use.

Soldered-down memory still needs to be supported in a future commit, as
stoney supports both DDR3 & DDR4.  A bug has been filed for support for
the upcoming Grunt platform.

BUG=b:67209686
TEST=Build and boot on Kahlee

Change-Id: Ife9bd90be9eb0ce0a7ce41d75cfef979b11e640b
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/21849
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Marc Jones <marc@marcjonesconsulting.com>
8 files changed