Remove duplicate checks for debugfs entry "DRRS capable:".

Fixes: 20af1084 ("drm/i915/display/debugfs: New entry "DRRS capable" to i915_drrs_status")
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240227123833.2799647-2-bhanuprakash.modem@intel.comSigned-off-by: Jani Nikula <jani.nikula@intel.com>