netbsd: disable pccons support

On NetBSD, pccons is (almost) dead: only remaining port is arc,
but only on some specific kernel, which is unlikely to be used
for running X.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1588>

include/meson.build

@@ -303,7 +303,6 @@ if host_machine.system() == 'kfreebsd'
 endif
 
 if host_machine.system() == 'netbsd'
-  supports_pccons = true
   supports_pcvt = true
   supports_wscons = true
   csrg_based = true