xwayland: Do not include sys/eventfd.h without DRI3

Now that we won't enable DRI3 if <sys/eventfd.h> is not available, there
is not point in trying to include that header without DRI3.

That allows to build Xwayland with GLAMOR enabled (without DRI3) on
platforms which do not support eventfd.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1523>

hw/xwayland/xwayland-glamor-gbm.c

@@ -33,7 +33,9 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <poll.h>
+#ifdef DRI3
 #include <sys/eventfd.h>
+#endif /* DRI3 */
 #include <sys/stat.h>
 #include <xf86drm.h>
 #include <drm_fourcc.h>

hw/xwayland/xwayland-present.c

@@ -31,7 +31,9 @@
 #endif
 #include <windowstr.h>
 #include <present.h>
+#ifdef DRI3
 #include <sys/eventfd.h>
+#endif /* DRI3 */
 
 #include "xwayland-present.h"
 #include "xwayland-screen.h"

hw/xwayland/xwayland-window-buffers.c

@@ -39,7 +39,9 @@
 #include "dri3.h"
 
 #include <poll.h>
+#ifdef DRI3
 #include <sys/eventfd.h>
+#endif
 #include "linux-drm-syncobj-v1-client-protocol.h"
 
 #define BUFFER_TIMEOUT 1 * 1000 /* ms */