Fix cppcheck error in example multi.c

Author: airween

examples/multiprocess_c/multi.c

@@ -38,7 +38,7 @@ RulesSet *rules = NULL;
 ModSecurity *modsec = NULL;
 
 
-void process_special_request (int j) {
+static void process_special_request (int j) {
     Transaction *transaction;
     transaction = msc_new_transaction(modsec, rules, NULL);
 
@@ -60,7 +60,7 @@ void process_special_request (int j) {
     msc_transaction_cleanup(transaction);
 }
 
-void process_request (int j) {
+static void process_request (int j) {
     int i;
 
     for (i = 0; i < REQUESTS_PER_PROCESS; i++) {