QXL is not shipped on the virtio-win iso, though it shipped in the .vfd images (and by extension /usr/share/virtio-win/drivers).
This seems to just be a historical oversight, so I've fixed this in the public build scripts now:
The next build should have QXL bits on the virtio-win.iso
Fixed in virtio-win-1.8.0-1.el7
QXL driver is in the virtio-win iso, this bug has been fixed in virtio-win-1.8.0-4.el7.
Above all,QE change this bug to verified.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.