e of 'device_create_file', declared with attribute warn_unused_result

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ð