headers_check fix: linux/hid.h

fix the following 'make headers_check' warnings:

  usr/include/linux/hid.h:69: extern's make no sense in userspace
  usr/include/linux/hid.h:76: extern's make no sense in userspace

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 81aa84d..fa8ee9c 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -791,6 +791,7 @@
 		__FILE__ , ## arg)
 #endif /* HID_FF */
 
+#ifdef __KERNEL__
 #ifdef CONFIG_HID_COMPAT
 #define HID_COMPAT_LOAD_DRIVER(name)	\
 /* prototype to avoid sparse warning */	\
@@ -804,6 +805,7 @@
 	extern void hid_compat_##name(void);	\
 	hid_compat_##name();			\
 } while (0)
+#endif /* __KERNEL__ */
 
 #endif