aco: run opt_algebraic in a loop

aco: run opt_algebraic in a loop

Totals from affected shaders:
SGPRS: 13920 -> 13656 (-1.90 %)
VGPRS: 12972 -> 12960 (-0.09 %)
Spilled SGPRs: 0 -> 0 (0.00 %)
Spilled VGPRs: 0 -> 0 (0.00 %)
Private memory VGPRs: 0 -> 0 (0.00 %)
Scratch size: 0 -> 0 (0.00 %) dwords per thread
Code Size: 1005680 -> 1000648 (-0.50 %) bytes
LDS: 91 -> 91 (0.00 %) blocks
Max Waves: 688 -> 688 (0.00 %)

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>