refactor(cbmc): make granule related buffers global

Change-Id: Ib31e826e9e98fd80d831f41408f32de274bfefad
Signed-off-by: Mate Toth-Pal <mate.toth-pal@arm.com>
diff --git a/lib/realm/src/granule.c b/lib/realm/src/granule.c
index d0f420b..e51df09 100644
--- a/lib/realm/src/granule.c
+++ b/lib/realm/src/granule.c
@@ -17,7 +17,7 @@
 #include <string.h>
 #include <utils_def.h>
 
-static struct granule granules[RMM_MAX_GRANULES];
+IF_NCBMC(static) struct granule granules[RMM_MAX_GRANULES];
 
 /*
  * Takes a valid pointer to a struct granule, and returns the granule physical