radeonsi: Bump number of allowed global buffers to 32

Fixes assertion failure/crash when running luxmark/luxball on clover.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108272


CC: mesa-stable@lists.freedesktop.org
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
(cherry picked from commit 06bf5672)