drm/msm/dpu: stop using raw IRQ indices in the kernel traces

In preparation to reworking IRQ indcies, stop using raw indices in
kernel traces. Instead use a pair of register index and bit. This
corresponds closer to the values in HW catalog.

Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/550935/
Link: https://lore.kernel.org/r/20230802100426.4184892-8-dmitry.baryshkov@linaro.org