drm/msm/sde: add support to access hw irqs regs depending on revision

Current code assumes that all the irqs registers
offsets can be access in all the hw revisions;
this is not the case for some targets that should
not access some of the irq registers.
This change adds the support to selectively remove
the irqs that are not supported in some of the
hw revisions.

Change-Id: Ic9d54864b515520bda39fad86c7b6cd29ff35db1
Signed-off-by: Ingrid Gallardo <ingridg@codeaurora.org>
Signed-off-by: Krishna Manikandan <mkrishn@codeaurora.org>