drm/edid: Remove defunct EDID_QUIRK_FIRST_DETAILED_PREFERRED

drm/edid: Remove defunct EDID_QUIRK_FIRST_DETAILED_PREFERRED

Looks like EDID_QUIRK_FIRST_DETAILED_PREFERRED never did anything.
Its counterpart in f86EdidModes.c is properly hooked up but somehow
that functionality was lost when it was copied into the kernel.

The concensus seems to be that this quirk is a bit misguided
anyway so let's nuke the leftovers.

For posterity here are some links to known cases:
* Proview AY765C
  https://bugs.freedesktop.org/show_bug.cgi?id=15160
* Unknown Acer
  https://bugzilla.redhat.com/show_bug.cgi?id=284231 (got the
  reference from xf86EdidModes.c)
* Peacock Ergovision 19 (only in xf86EdidModes.c)
  https://bugzilla.redhat.com/show_bug.cgi?id=492359
* Philips 107p5 CRT
  "Reported on xorg@ with pastebin", didn't find the mail(s)

Cc: Adam Jackson <ajax@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190322174244.23945-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>