feat(fvp): add plat API to validate that passed region is non-secure

Added a platform function to check passed region is within
the Non-Secure region of DRAM.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: Ie5808fa6a1b6e6bc99f4185fa8acc52af0d5f14d
diff --git a/include/plat/common/plat_drtm.h b/include/plat/common/plat_drtm.h
index 754fa1a..e96e719 100644
--- a/include/plat/common/plat_drtm.h
+++ b/include/plat/common/plat_drtm.h
@@ -64,4 +64,11 @@
 int plat_set_drtm_error(uint64_t error_code);
 int plat_get_drtm_error(uint64_t *error_code);
 
+/*
+ * Platform-specific function to ensure passed region lies within
+ * Non-Secure region of DRAM
+ */
+int plat_drtm_validate_ns_region(uintptr_t region_start,
+				 size_t region_size);
+
 #endif /* PLAT_DRTM_H */