ARM: 6101/1: nomadik-gpio: don't enable in set_type

On this peripheral, setting the trigger type enables the interrupt, and
the current set_type() implementation unconditionally enables the
interrupt, even if it is called when the interrupt is disabled.  Fix
set_type() to:

 - if the interrupt is disabled, defer the actual trigger setting to
   when it is unmasked

 - if the interrupt is enabled, change the type immediately by clearing
   the old type and then re-enabling with the new type.

Acked-by: Alessandro Rubini <rubini@unipv.it>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>