drm: Remove the 'mode' argument from drm_select_eld()

drm_select_eld() doesn't look at the passed in mode, so don't pass it
in.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>