Declare debug_level to 0 in ossec-agentd for NIX

src/client-agent/main.c

@@ -36,7 +36,7 @@ int main(int argc, char **argv)
 {
     int c = 0;
     int test_config = 0;
-    int debug_level;
+    int debug_level = 0;
 
     char *dir = DEFAULTDIR;
     char *user = USER;