[glib/fix.unix.nonlinux.ci] gio/tests/pollable.c: Fix build on non-Linux UNIX

[Chun-wei Fan <fanchunwei src gnome org>]

commit cf02c280ff255f8af04f3bc76d142db92ddd8a01
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Sat Feb 27 10:53:53 2021 +0800

    gio/tests/pollable.c: Fix build on non-Linux UNIX
    
    For non-Linux UNIX systems, the label 'close_libutil:' in
    'test_pollable_unix_pty()' will have no statement that goes with that
    label.  Just do a 'return' on non-Linux UNIX systems.

 gio/tests/pollable.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/gio/tests/pollable.c b/gio/tests/pollable.c
index 01049788b..d57c4733a 100644
--- a/gio/tests/pollable.c
+++ b/gio/tests/pollable.c
@@ -225,6 +225,8 @@ test_pollable_unix_pty (void)
 close_libutil:
 #ifdef __linux__
   dlclose (handle);
+#else
+  return;
 #endif
 }