cs5535-gpio.c has been split into two, with various setup moved
into cs5535-mfd.c.  Given that cs5535-gpio will not load without
the -mfd part, lets make that dependency explicit in Kconfig
Signed-off-by: NEd Wildgoose <kernel@wildgooses.com>
Acked-by: NAndres Salomon <dilinger@queued.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>