amd/stoneyridge: Increase SMM reserved memory

Add 64KB to the reserved memory used for stage_cache.  This corrects
an error observed when using a debug build of the AGESA blob.

Messages on initial boot
  AGESA: Saving stage to cache
  Error: Can't add stage_cache 57a9e101 to imd
and during resume
  AGESA: Loading stage from cache
  Error: Can't find stage_cache 57a9e101 in imd

TEST=boot/suspend/resume Grunt with debug and release builds
BUG=b:79154155

Change-Id: I3f27059fcef37e335d0301142ba4dedb3809e369
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/26386
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/amd/stoneyridge/Kconfig b/src/soc/amd/stoneyridge/Kconfig
index 5e4800f..1af3ccb 100644
--- a/src/soc/amd/stoneyridge/Kconfig
+++ b/src/soc/amd/stoneyridge/Kconfig
@@ -300,7 +300,7 @@
 
 config SMM_RESERVED_SIZE
 	hex
-	default 0x140000
+	default 0x150000
 
 config ACPI_CPU_STRING
 	string