xfree86: Remove -flippixels

No supported driver supports 1bpp anymore, nor has in a very long time.
This option only worked with vgahw anyway.

Signed-off-by: Adam Jackson <ajax@redhat.com>
1 job for flippixels in 3 minutes and 19 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #25686
job

00:03:19