Fix MISRA rule 8.4 Part 1

Rule 8.4: A compatible declaration shall be visible when
          an object or function with external linkage is defined

Fixed for:
	make DEBUG=1 PLAT=fvp LOG_LEVEL=50 all

Change-Id: I7c2ad3f5c015411c202605851240d5347e4cc8c7
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index 66efe45..0a80814 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -237,4 +237,8 @@
 		uint32_t cookie_lo,
 		void *handle);
 
+/* global variables */
+extern plat_psci_ops_t plat_arm_psci_pm_ops;
+extern const mmap_region_t plat_arm_mmap[];
+
 #endif /* __PLAT_ARM_H__ */