fix a memory leak in device state

The callback handle_statechange (pbx.c) fails to release its data
pointer, leaking memory in the process.

Reported by: tzafrir
Patches:
      18735_pbx_free_callback.diff uploaded by tzafrir (license 46)

Review: https://reviewboard.asterisk.org/r/1110/



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@308371 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/pbx.c

@@ -4348,9 +4348,11 @@ static int handle_statechange(void *datap)
 	struct ao2_iterator cb_iter;
 
 	if (ao2_container_count(hintdevices) == 0) {
+		ast_free(sc);
 		return 0;
 	}
 	if (!(cmpdevice = ast_malloc(sizeof(*cmpdevice) + strlen(sc->dev)))) {
+		ast_free(sc);
 		return -1;
 	}
 	strcpy(cmpdevice->hintdevice, sc->dev);
@@ -4414,6 +4416,7 @@ static int handle_statechange(void *datap)
 	if (cmpdevice) {
 		ast_free(cmpdevice);
 	}
+	ast_free(sc);
 	return 0;
 }