nir/algebraic: Lower some bfi with two constant sources

nir/algebraic: Lower some bfi with two constant sources

All Haswell and newer Intel platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 19907054 -> 19906882 (<.01%)
instructions in affected programs: 8103 -> 7931 (-2.12%)
helped: 52 / HURT: 0

total cycles in shared programs: 855779334 -> 855781791 (<.01%)
cycles in affected programs: 724201 -> 726658 (0.34%)
helped: 38 / HURT: 7

total sends in shared programs: 1039308 -> 1039302 (<.01%)
sends in affected programs: 162 -> 156 (-3.70%)
helped: 2 / HURT: 0

No shader-db changes on any older Intel platforms.

All Intel platforms had similar restuls. (Ice Lake shown)
Totals:
Instrs: 153117340 -> 152825222 (-0.19%); split: -0.19%, +0.00%
Cycles: 15011904351 -> 15014072944 (+0.01%); split: -0.04%, +0.05%
Send messages: 7711509 -> 7711421 (-0.00%)
Spill count: 100745 -> 99907 (-0.83%); split: -0.85%, +0.02%
Fill count: 203684 -> 202459 (-0.60%); split: -0.62%, +0.02%
Scratch Memory Size: 4403200 -> 4376576 (-0.60%)

Totals from 18603 (2.81% of 662496) affected shaders:
Instrs: 5258303 -> 4966185 (-5.56%); split: -5.56%, +0.00%
Cycles: 447391388 -> 449559981 (+0.48%); split: -1.29%, +1.77%
Send messages: 559231 -> 559143 (-0.02%)
Spill count: 5009 -> 4171 (-16.73%); split: -17.17%, +0.44%
Fill count: 8769 -> 7544 (-13.97%); split: -14.33%, +0.36%
Scratch Memory Size: 194560 -> 167936 (-13.68%)

Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19968>