hw/xwin/glx: Fix logging about WGL pxfs with overlays

Signed-off-by: Jon Turney <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>
1 job for glx-fixes in 1 minute and 52 seconds (queued for 19 seconds)
Status Job ID Name Coverage
  Test
passed #25202
job

00:01:52