gpio: do not set up hardware for IRQ_TYPE_NONE

Some GPIO irqchip drivers exploit the irqdomain mapping
function to set up the IRQ default type in the hardware,
make sure that if we pass IRQ_TYPE_NONE, no hardware setup
whatsoever takes place (this should be the norm) until
later when the IRQ gets utilized.

Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: linux-omap <linux-omap@vger.kernel.org>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Javier Martinez Canillas <javier@dowhile0.org>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>