Use correct framebuffer driver on FreeBSD

Use the correct framebuffer driver on FreeBSD, wich is different from
the framebuffer driver on Linux.
3 jobs for zeising/fbsd-autoconfig in 7 minutes and 1 second
latest
Status Name Job ID Coverage
  Docker Image
passed debian-testing #637566

00:01:28

 
  Build And Test
passed autotools-build-and-test #637567

00:05:31

passed meson-build-and-test #637568

00:01:22