[PATCH v1 0/3] drm/msm/dpu: rework irq handling

[Dmitry Baryshkov]

Simplify IRQ handling. dpu_irq_map is a huge table consisting of all
possible IRQ entries (including a plenty of 'reserved' = not existing
IRQs). It is always used to lookup the interrupt index (in the table)
and then to use this index to lookup related interrupt register and
mask. For the long period of time these indices had 1:1 correspondence
to register/mask pairs. SC7280 introduced 'additional' IRQs removing
this correpondence.

Replace all IRQ lookup with stable irq indices, which correponds
directly to the register/bit pair. The dpu_irq_map table is used only
for the lookup of the irq index.

Changes since RFC:
 - rebase on top of msm/msm-next to include SC7280 changes.