vc/amd/pi/00670F00/binaryPI: cache the AGESA dispatcher

Instead of repeatedly walking cbfs for the AGESA blob and parsing it
cache the resulting dispatcher value. There's only one dispatcher table
so use it. The resulting change is that this work is done one time per
stage.

BUG=b:70401101
TEST=Booted and noted only one lookup per stage.

Change-Id: Iaa4aecc384108d66d7c68fc5fb9ac1c3f40da905
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/22789
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Justin TerAvest <teravest@chromium.org>
3 files changed