Revert "irqchip: qcom-pdc: Remove irq_disable callback"

This reverts commit e5cd52c7.

After Commit e5cd52c7 ("irqchip: qcom-pdc: Remove irq_disable
callback") irq_mask callback is not completely masking irq at PDC in
case if the interrupt is marked for wakeup. Leaving it unmasked at PDC
may generate unwanted wakeups.

Remove irq_set_wake and use irq_enable/disable callbacks to manage
interrupts at PDC.

Change-Id: Ife0026e612b8136ef3c26023fc0bda7b5286bae8
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>