platform: Add new api to get MSM_SHARED_BASE

Add a new api to get MSM_SHARED_BASE address from platform.
MSM_SHARED_BASE address is dependent on platform subtype and
hence is different for some platform variants.

Change-Id: I307d2110984e788aeeac2bcaa9f185ce2e2c92f4
diff --git a/platform/msm_shared/smem.h b/platform/msm_shared/smem.h
index 1e533f9..15874f0 100644
--- a/platform/msm_shared/smem.h
+++ b/platform/msm_shared/smem.h
@@ -45,6 +45,8 @@
 #define _SMEM_RAM_PTABLE_MAGIC_1        0x9DA5E0A8
 #define _SMEM_RAM_PTABLE_MAGIC_2        0xAF9EC4E2
 
+#define SMEM_TARGET_INFO_IDENTIFIER     0x49494953
+
 enum smem_ram_ptable_version
 {
 	SMEM_RAM_PTABLE_VERSION_0,