drm/i915: remove extra new line on pipe_config mismatch

The new line is already added by pipe_config_mismatch(), so the callers
shouldn't add it.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191011010907.103309-5-lucas.demarchi@intel.com