Enable flag in http_client_body for http request body callback

src/detect-http-client-body.c

@@ -223,6 +223,8 @@ int DetectHttpClientBodySetup(DetectEngineCtx *de_ctx, Signature *s, char *arg)
     /* flag the signature to indicate that we scan the app layer data */
     s->flags |= SIG_FLAG_APPLAYER;
     s->alproto = ALPROTO_HTTP;
+    /* enable http request body callback in the http app layer parser */
+    AppLayerHtpEnableRequestBodyCallback();
 
     return 0;