xfree86: On Linux, while only seat0 can have TTYs, don't assmume all seat0s have TTYs

4 jobs for fixnottyseat0 in 2 minutes and 29 seconds (queued for 22 seconds)
Status Name Job ID Coverage
  Docker Image
passed debian-buster #15543938

00:00:13

 
  Build And Test
passed meson #15543939

00:02:15

passed meson-noglamor #15543940

00:01:52

passed mingw-cross-build #15543941

00:00:42