cbmem: add CBMEM_ID_ROMSTAGE_INFO id

Introduce a new cbmem id to indicate romstage information. Proper
coordination with ramstage and romstage can use this cbmem entity
to communicate between one another.

Change-Id: Id785f429eeff5b015188c36eb932e6a6ce122da8
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2790
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>

src/include/cbmem.h

@@ -56,6 +56,7 @@
 #define CBMEM_ID_CONSOLE	0x434f4e53
 #define CBMEM_ID_ELOG		0x454c4f47
 #define CBMEM_ID_COVERAGE	0x47434f56
+#define CBMEM_ID_ROMSTAGE_INFO	0x47545352
 #define CBMEM_ID_NONE		0x00000000
 
 #ifndef __ASSEMBLER__