nvc0/ir: fix ubo max clamp, reset file index

nvc0/ir: fix ubo max clamp, reset file index

We just increased the max UBO, so we should also increase the clamp that
we do for robustness. Similarly, as we're including the fileIndex in the
new indirect value, we should reset fileIndex to 0 so that it is not
added in a second time.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Cc: mesa-stable@lists.freedesktop.org