drm/i915/psr: Drop test for EDP in CRTC when forcing commit

If has_psr is set it means that CRTC has a EDP panel attached so the
EDP check is redundant and can be dropped.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190308000050.6226-4-jose.souza@intel.com