randr: swap num-preferred field on RRGetOutputInfo reply

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=88614
Signed-off-by: Carlos Sánchez de La Lama <csanchezdll@gmail.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

randr/rroutput.c

@@ -487,6 +487,7 @@ ProcRRGetOutputInfo(ClientPtr client)
         swapl(&rep.mmHeight);
         swaps(&rep.nCrtcs);
         swaps(&rep.nModes);
+        swaps(&rep.nPreferred);
         swaps(&rep.nClones);
         swaps(&rep.nameLength);
     }