hwmon: fix freeing of gpio_data and irq

If already requested, gpio_data and irq should be freed in the case of an
error.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>