add busybox rmdir for develsystems

Config.in

@@ -37,6 +37,7 @@ config ADK_DEVELSYSTEM
 	select BUSYBOX_INSTALL
 	select BUSYBOX_MKTEMP
 	select BUSYBOX_UNZIP
+	select BUSYBOX_RMDIR
 	select BUSYBOX_TAC
 	select BUSYBOX_TEE
 	select BUSYBOX_WGET