[PATCH] HID read busywait fix

Make a read of a HID device block until data is available.  Without it, the
read goes into a busy-wait loop until data is available.

Cc: Greg KH <greg@kroah.com>
Acked-by: Vojtech Pavlik <vojtech@suse.cz>
Cc: Dmitry Torokhov <dtor_core@ameritech.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>