radv: Set partial_vs_wave for pipelines with just GS, not tess.

Looking at -pro we need to enable it for pipelines with just a
GS too.

This seems to reduce the hangs from
https://bugs.freedesktop.org/show_bug.cgi?id=109242

 on a RX 550 to
the point where I can't reproduce, after the false start with the
wd_switch_on_eop patch due to flakiness.

(but people are reporting it does not fix the issue completely for
 them on polaris 11)

CC: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
(cherry picked from commit 568e7a29)