MLE service releases CCM library in error case (ARMmbed#1719)

CCM libary is relased in error cases to avoid resource lock up.

Author: Arto Kinnunen

source/Service_Libs/mle_service/mle_service.c

@@ -420,6 +420,7 @@ static buffer_t *mle_service_message_security_decode(buffer_t *buf, mle_security
     if (!ccm_ptr) {
         return buffer_free(buf);
     } else if (ccm_ptr->mic_len >= payload_len) {
+        ccm_process_run(NULL);
         return buffer_free(buf);
     }
 
@@ -507,6 +508,7 @@ static buffer_t *mle_message_security_header_set(buffer_t *buf,service_instance_
             } else {
                 tr_warn("Security header alloc fail");
                 buf = (buffer_t *) 0;
+                ccm_process_run(NULL);
                 return buf;
             }
         }