drm/i915/dmc_wl: Show description string for enable_dmc_wl

drm/i915/dmc_wl: Show description string for enable_dmc_wl

We already provide the value resulting from sanitization of
enable_dmc_wl in dmesg, however the reader will need to either have the
meanings memorized or look them up in the parameter's documentation.
Let's make things easier by providing a short human-readable name for
the parameter in dmesg.

Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Dnyaneshwar Bhadane <dnyaneshwar.bhadane@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241219221429.109668-3-gustavo.sousa@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>