virtio_9p.h needs <linux/types.h>

Found with makes headers_check:
include/linux/virtio_9p.h:15: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Fang Wenqi <antonf@turbolinux.com.cn>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

include/linux/virtio_9p.h

@@ -4,6 +4,7 @@
  * compatible drivers/servers. */
 #include <linux/virtio_ids.h>
 #include <linux/virtio_config.h>
+#include <linux/types.h>
 
 /* The feature bitmap for virtio 9P */