Fix MISRA rule 8.4 in common code

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

Change-Id: I26e042cb251a6f9590afa1340fdac73e42f23979
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
diff --git a/include/lib/cpus/errata_report.h b/include/lib/cpus/errata_report.h
index 14f2407..d2138bf 100644
--- a/include/lib/cpus/errata_report.h
+++ b/include/lib/cpus/errata_report.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -20,6 +20,9 @@
 static inline void print_errata_status(void) {}
 #endif
 
+void errata_print_msg(unsigned int status, const char *cpu, const char *id);
+int errata_needs_reporting(spinlock_t *lock, uint32_t *reported);
+
 #endif /* __ASSEMBLY__ */
 
 /* Errata status */