testsuite: Add a suite for tests that require /dev/udmabuf

On GTK's official upstream CI, all Linux runners are meant to have
/dev/udmabuf available, so this should pass. On developer machines or
downstream build environments, this can't be guaranteed (not all kernel
configurations offer that device, and on those that do, an autobuilder
might not have access to it) so make it possible to skip this with
`--no-suite=needs-udmabuf`.

Any future tests that rely on /dev/udmabuf (as opposed to using it for
optional better coverage if available, like replay-node does) can be
aded to the same suite.

Signed-off-by: Simon McVittie <smcv@debian.org>

testsuite/gdk/meson.build

@@ -37,6 +37,9 @@ if os_linux
   tests += [
     { 'name': 'dmabuf-support',
       'sources': [ 'udmabuf.c' ],
+      # This needs to pass on upstream Gitlab-CI, but cannot be guaranteed
+      # to work on developer machines or downstream build environments
+      'suites': [ 'needs-udmabuf' ],
     },
   ]
 endif