nir/algebraic: Optimize some b2i involved in masking operations

nir/algebraic: Optimize some b2i involved in masking operations

v2: Remove the ineg from the b2i in the ior pattern.  Suggested by
Jason.

All Ivy Bridge and newer Intel platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 19914441 -> 19914369 (<.01%)
instructions in affected programs: 63507 -> 63435 (-0.11%)
helped: 24 / HURT: 0

total cycles in shared programs: 853869766 -> 853851470 (<.01%)
cycles in affected programs: 10551542 -> 10533246 (-0.17%)
helped: 24 / HURT: 0

All Intel platforms had similar results. (Ice Lake shown)
Instructions in all programs: 141163061 -> 141092683 (-0.0%)
Instructions helped: 14103
Instructions hurt: 55

Cycles in all programs: 9132376195 -> 9133183045 (+0.0%)
Cycles helped: 13775
Cycles hurt: 380

Spills in all programs: 18286 -> 18284 (-0.0%)
Spills helped: 1

Fills in all programs: 30647 -> 30643 (-0.0%)
Fills helped: 1

Gained: 133
Lost: 130

Acked-by: Jesse Natalie <jenatali@microsoft.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Tested-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15121>