anv: Accurately advertise dynamic descriptor limits

The number of dynamic descriptors is limited by both the number of
descriptors and the total number of dynamic things.  Because there isn't
a single "maximum dynamic things" limit, we need to divide by two so
that they can create the maximum of both UBOs and SSBOs.

Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Cc: "17.0 13.0" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit 5e44ef4a76d9a3681fb6be605319250d4ab800ee)
1 file changed