drm/msm/dpu: Reserve resources for CWB

drm/msm/dpu: Reserve resources for CWB

Add support for RM to reserve dedicated CWB PINGPONGs and CWB muxes

For concurrent writeback, even-indexed CWB muxes must be assigned to
even-indexed LMs and odd-indexed CWB muxes for odd-indexed LMs. The same
even/odd rule applies for dedicated CWB PINGPONGs.

Track the CWB muxes in the global state and add a CWB-specific helper to
reserve the correct CWB muxes and dedicated PINGPONGs following the
even/odd rule.

Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/637495/
Link: https://lore.kernel.org/r/20250214-concurrent-wb-v6-7-a44c293cf422@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>