freedreno/a2xx: ir2: fix lowering of instructions after float lowering

Some instructions generated by int/bool float lowering need to be lowered
by opt_algebraic.

Fixes: 43dbd7d6

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit 3516a90a)