MINOR: stream-int: rename si_applet_done() to si_applet_wake_cb()

This function is a callback made only for calls from the applet handler.
Rename it to remove confusion. It's currently called from the Lua code
but that's not correct, we should call the notify and update functions
instead otherwise it will not enable the applet again.
diff --git a/src/applet.c b/src/applet.c
index 42d894d..bc8972e 100644
--- a/src/applet.c
+++ b/src/applet.c
@@ -61,7 +61,7 @@
 		si_applet_stop_put(si);
 
 		curr->applet->fct(curr);
-		si_applet_done(si);
+		si_applet_wake_cb(si);
 
 		if (applet_run_queue.n == &curr->runq) {
 			/* curr was left in the list, move it back to the active list */