irqchip: qcom-pdc: Remove irq_disable callback

Remove irq_disable callback to allow lazy disable for pdc interrupts.
Add irq_set_wake callback to set interrupt in HW when drivers mark
interrupt for wakeup. Interrupt will be cleared in HW during lazy
disable if its not marked for wakeup.

Change-Id: Ic6fc6392248e473ac489bd83423034be5e20f78f
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>