USB: common: debug: add needed kernel.h include

drivers/usb/common/debug.c was only including one usb .h file, which
would then accidentally drag in other .h files that were really needed.
Fix up the implict dependancy by correctly adding kernel.h to the file.

Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: gregkh

drivers/usb/common/debug.c

@@ -8,6 +8,7 @@
  *	    Sebastian Andrzej Siewior <[email protected]>
  */
 
+#include <linux/kernel.h>
 #include <linux/usb/ch9.h>
 
 static void usb_decode_get_status(__u8 bRequestType, __u16 wIndex,