drm/drm_connector: Provide short description of param 'supported_colorspaces'

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/drm_connector.c:2215: warning: Function parameter or member 'supported_colorspaces' not described in 'drm_mode_create_hdmi_colorspace_property'
 drivers/gpu/drm/drm_connector.c:2239: warning: Function parameter or member 'supported_colorspaces' not described in 'drm_mode_create_dp_colorspace_property'
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230824073710.2677348-17-lee@kernel.orgSigned-off-by: Maxime Ripard <mripard@kernel.org>

drivers/gpu/drm/drm_connector.c

@@ -2203,6 +2203,7 @@ static int drm_mode_create_colorspace_property(struct drm_connector *connector,
 /**
  * drm_mode_create_hdmi_colorspace_property - create hdmi colorspace property
  * @connector: connector to create the Colorspace property on.
+ * @supported_colorspaces: bitmap of supported color spaces
  *
  * Called by a driver the first time it's needed, must be attached to desired
  * HDMI connectors.
@@ -2227,6 +2228,7 @@ EXPORT_SYMBOL(drm_mode_create_hdmi_colorspace_property);
 /**
  * drm_mode_create_dp_colorspace_property - create dp colorspace property
  * @connector: connector to create the Colorspace property on.
+ * @supported_colorspaces: bitmap of supported color spaces
  *
  * Called by a driver the first time it's needed, must be attached to desired
  * DP connectors.