freedreno/ir3: Use nir_opt_idiv_const

Notably reduces the number of instructions in manhattan31/377 by 101:

instructions helped:   shaders/closed/android/gfxbench/manhattan31/377.shader_test CL: 1700 -> 1599 (-5.94%)

total instructions in shared programs: 1713536 -> 1713313 (-0.01%)
instructions in affected programs: 7635 -> 7412 (-2.92%)
helped: 12
HURT: 9

total nops in shared programs: 377253 -> 377188 (-0.02%)
nops in affected programs: 3170 -> 3105 (-2.05%)
helped: 13
HURT: 8

total non-nops in shared programs: 1336283 -> 1336125 (-0.01%)
non-nops in affected programs: 3134 -> 2976 (-5.04%)
helped: 12
HURT: 4

total mov in shared programs: 66642 -> 66641 (<.01%)
mov in affected programs: 145 -> 144 (-0.69%)
helped: 1
HURT: 4

total cov in shared programs: 20215 -> 20223 (0.04%)
cov in affected programs: 64 -> 72 (12.50%)
helped: 0
HURT: 8

total dwords in shared programs: 3650282 -> 3649876 (-0.01%)
dwords in affected programs: 11222 -> 10816 (-3.62%)
helped: 12
HURT: 0

total constlen in shared programs: 246636 -> 246656 (<.01%)
constlen in affected programs: 72 -> 92 (27.78%)
helped: 0
HURT: 5

total cat0 in shared programs: 411874 -> 411809 (-0.02%)
cat0 in affected programs: 3414 -> 3349 (-1.90%)
helped: 13
HURT: 8

total cat1 in shared programs: 87109 -> 87116 (<.01%)
cat1 in affected programs: 398 -> 405 (1.76%)
helped: 1
HURT: 12

total cat2 in shared programs: 797105 -> 797030 (<.01%)
cat2 in affected programs: 1619 -> 1544 (-4.63%)
helped: 12
HURT: 0

total cat3 in shared programs: 348412 -> 348322 (-0.03%)
cat3 in affected programs: 404 -> 314 (-22.28%)
helped: 12
HURT: 0

total sstall in shared programs: 133300 -> 133302 (<.01%)
sstall in affected programs: 73 -> 75 (2.74%)
helped: 0
HURT: 1

total (ss) in shared programs: 36137 -> 36139 (<.01%)
(ss) in affected programs: 54 -> 56 (3.70%)
helped: 0
HURT: 2

total systall in shared programs: 323494 -> 323624 (0.04%)
systall in affected programs: 1591 -> 1721 (8.17%)
helped: 4
HURT: 2

total (sy) in shared programs: 14306 -> 14308 (0.01%)
(sy) in affected programs: 46 -> 48 (4.35%)
helped: 0

HURT: 2
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18085>

src/freedreno/ir3/ir3_nir.c

@@ -355,7 +355,8 @@ ir3_finalize_nir(struct ir3_compiler *compiler, nir_shader *s)
    nir_lower_idiv_options idiv_options = {
       .allow_fp16 = true,
    };
-   const bool idiv_progress = OPT(s, nir_lower_idiv, &idiv_options);
+   bool idiv_progress = OPT(s, nir_opt_idiv_const, 8);
+   idiv_progress |= OPT(s, nir_lower_idiv, &idiv_options);
 
    if (idiv_progress)
       ir3_optimize_loop(compiler, s);