fix(misra): fix MISRA-C:2012 8.7 in logger.c

Signed-off-by: AlexeiFedorov <Alexei.Fedorov@arm.com>
Change-Id: I6d963dc9678c61344a6d3459d9e1b5ebcac635c6
diff --git a/runtime/rsi/logger.c b/runtime/rsi/logger.c
index c4b5c9e..aca1941 100644
--- a/runtime/rsi/logger.c
+++ b/runtime/rsi/logger.c
@@ -50,7 +50,7 @@
 
 #define RSI_STATUS_STRING(_id)[RSI_##_id] = #_id
 
-const char *rsi_status_string[] = {
+static const char *rsi_status_string[] = {
 	RSI_STATUS_STRING(SUCCESS),
 	RSI_STATUS_STRING(ERROR_INPUT),
 	RSI_STATUS_STRING(ERROR_STATE),