CLEANUP: stream-int: remove obsolete function si_applet_call()

This one is not used anymore and is bogus due to the way applets
now work. Remove it instead of fixing it before someone finds it
fun to use it.
diff --git a/include/proto/stream_interface.h b/include/proto/stream_interface.h
index 8c7a950..47acb76 100644
--- a/include/proto/stream_interface.h
+++ b/include/proto/stream_interface.h
@@ -221,21 +221,6 @@
 	return objt_appctx(si->end);
 }
 
-/* Call the applet's main function when an appctx is attached to the stream
- * interface. Returns zero if no call was made, or non-zero if a call was made.
- */
-static inline int si_applet_call(struct stream_interface *si)
-{
-	struct appctx *appctx;
-
-	appctx = si_appctx(si);
-	if (appctx) {
-		appctx->applet->fct(appctx);
-		return 1;
-	}
-	return 0;
-}
-
 /* call the applet's release function if any. Needs to be called upon close() */
 static inline void si_applet_release(struct stream_interface *si)
 {