headers_check fix: linux/phonet.h

fix the following 'make headers_check' warning:

  usr/include/linux/phonet.h:50: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
diff --git a/include/linux/phonet.h b/include/linux/phonet.h
index 4157faa..ee5e3c9 100644
--- a/include/linux/phonet.h
+++ b/include/linux/phonet.h
@@ -23,6 +23,8 @@
 #ifndef LINUX_PHONET_H
 #define LINUX_PHONET_H
 
+#include <linux/types.h>
+
 /* Automatic protocol selection */
 #define PN_PROTO_TRANSPORT	0
 /* Phonet datagram socket */