amd/common/pi: Remove AGESA support files from bootblock

The stoneyridge bootblock no longer makes AGESA calls.  Remove the
support files from the bootblock build.

TEST=boot Grunt

Change-Id: I14d2336d5fb766a1acf5e812337ae0ab3ca4a6c1
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/27255
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

src/soc/amd/common/block/pi/Makefile.inc

@@ -1,9 +1,5 @@
 ifeq ($(CONFIG_SOC_AMD_COMMON_BLOCK_PI),y)
 
-bootblock-y += agesawrapper.c
-bootblock-y += def_callouts.c
-bootblock-y += heapmanager.c
-
 romstage-y += agesawrapper.c
 romstage-y += def_callouts.c
 romstage-y += heapmanager.c