drm/msm/dpu: Print interrupt index in addition to the mask

The mask only describes the `irq_idx % 32` part, making it generally
impossible to deduce what interrupt is being enabled/disabled.  Since
`debug/core_irq` in debugfs (and other prints) also include the full
`DPU_IRQ_IDX()` value, print the same full value here for easier
correlation instead of only adding the `irq_idx / 32` part.

Furthermore, make the dbgstr messages more consistent.

Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Martin Botka <martin.botka@somainline.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/512460/
Link: https://lore.kernel.org/r/20221121222456.437815-1-marijn.suijten@somainline.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>