nv50/ir: set neg modifiers on min/max args

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=86618
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: "10.4 10.3" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit 7d07083cfdff4bdbeca9ac36c2127cb6a26be207)
nv50,nvc0: actually check constbufs for invalidation

The number of vertex buffers has nothing to do with the number of bound
constbufs.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: "10.4 10.3" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit e80a0a7d9a02fe12dedfb2e221358af620759c28)
nv50,nvc0: buffer resources can be bound as other things down the line

res->bind is not an indicator of how the resource is currently bound.
buffers can be rebound across different binding points without changing
underlying storage.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: "10.4 10.3" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit fecae4625cf9a132bb3fbfeaadbbf3db68be6024)