fix(rmm): fix static checks warnings

Fixes:
WARNING: static const char * array should probably be
static const char * const
in handler.c and logger.c

Signed-off-by: AlexeiFedorov <Alexei.Fedorov@arm.com>
Change-Id: I40f27b5a2e20c36c58afbc81459fc7b69897190b
diff --git a/runtime/rsi/logger.c b/runtime/rsi/logger.c
index f392d15..fd88109 100644
--- a/runtime/rsi/logger.c
+++ b/runtime/rsi/logger.c
@@ -50,7 +50,7 @@
 
 #define RSI_STATUS_STRING(_id)[RSI_##_id] = #_id
 
-static const char *rsi_status_string[] = {
+static const char * const rsi_status_string[] = {
 	RSI_STATUS_STRING(SUCCESS),
 	RSI_STATUS_STRING(ERROR_INPUT),
 	RSI_STATUS_STRING(ERROR_STATE),