signature: Fix leak in urilen parsing

cf #4254

(cherry picked from commit 47dd9a5ebc)

src/detect-urilen.c

@@ -220,13 +220,15 @@ error:
     if (urilend)
         SCFree(urilend);
     if (arg1 != NULL)
-        SCFree(arg1);
+        pcre_free_substring(arg1);
     if (arg2 != NULL)
-        SCFree(arg2);
+        pcre_free_substring(arg2);
     if (arg3 != NULL)
-        SCFree(arg3);
+        pcre_free_substring(arg3);
     if (arg4 != NULL)
-        SCFree(arg4);
+        pcre_free_substring(arg4);
+    if (arg5 != NULL)
+        pcre_free_substring(arg5);
     return NULL;
 }
 
@@ -745,4 +747,4 @@ void DetectUrilenRegisterTests(void)
     UtRegisterTest("DetectUrilenSetpTest01", DetectUrilenSetpTest01);
     UtRegisterTest("DetectUrilenSigTest01", DetectUrilenSigTest01);
 }
-#endif /* UNITTESTS */
+#endif /* UNITTESTS */