nvc0/ir: fix LSB/BFE/BFI implementations

Overwriting the src register is a very bad idea - it logically maps onto
the TGSI registers, and so is effectively overwriting the source values.

Reported-by: Boyan Ding <boyan.j.ding@gmail.com>
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: mesa-stable@lists.freedesktop.org
(cherry picked from commit 60f5766db48fe81f55f4b7be47c2be27bdbe2c10)
1 file changed