drm/msm/mdss: reuse defined bitfields for UBWC 2.0

Follow other msm_mdss_setup_ubwc_dec_nn functions and use individual
bits instead of just specifying the value to be programmed to the
UBWC_STATIC register.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/626373/
Link: https://lore.kernel.org/r/20241127-msm-mdss-ubwc-v3-2-9782a7c2b023@linaro.org