drm/connector: hdmi: Compute bpc and format automatically

Now that we have all the infrastructure needed, we can add some code
that will, for a given connector state and mode, compute the best output
format and bpc.

The algorithm is equivalent to the one already found in i915 and vc4.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-15-c5af16c3aae2@kernel.org


Signed-off-by: Maxime Ripard <mripard@kernel.org>