drm/msm/dpu: shift IRQ indices by 1

drm/msm/dpu: shift IRQ indices by 1

In order to simplify IRQ declarations, shift IRQ indices by 1. This
makes 0 the 'no IRQ' value. Thanks to this change, we do no longer have
to explicitly set the 'no interrupt' fields in catalog structures.

Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/550938/
Link: https://lore.kernel.org/r/20230802100426.4184892-9-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>