ia64: remove ARCH_WANT_OPTIONAL_GPIOLIB

This symbols is not needed to get access to selecting the
GPIOLIB anymore: any arch can select GPIOLIB.

Cc: Michael Büsch <m@bues.ch>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

arch/ia64/Kconfig

@@ -39,7 +39,6 @@ config IA64
 	select GENERIC_PENDING_IRQ if SMP
 	select GENERIC_IRQ_SHOW
 	select GENERIC_IRQ_LEGACY
-	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select GENERIC_IOMAP
 	select GENERIC_SMP_IDLE_THREAD