detect/luaxform: fix allowed lua rules check

Meant to be enabled by default, but wasn't.

(cherry picked from commit da87bd6)

Author: victorjulien

src/detect-transform-luaxform.c

@@ -261,8 +261,7 @@ static int DetectTransformLuaxformSetup(DetectEngineCtx *de_ctx, Signature *s, c
     /* First check if Lua rules are enabled, by default Lua in rules
      * is disabled. */
     int enabled = 0;
-    (void)SCConfGetBool("security.lua.allow-rules", &enabled);
-    if (!enabled) {
+    if (SCConfGetBool("security.lua.allow-rules", &enabled) == 1 && !enabled) {
         SCLogError("Lua rules disabled by security configuration: security.lua.allow-rules");
         SCReturnInt(-1);
     }