nir/range_analysis: Fix analysis of fmin, fmax, or fsat with NaN source

nir/range_analysis: Fix analysis of fmin, fmax, or fsat with NaN source

Recall that when either value is NaN, fmax will pick the other value.
This means the result range of the fmax will either be the "ideal"
result range (calculated above) or the range of the non-NaN value.

Previously, something like fmax({gt_zero}, {lt_zero, is_a_number}) would
return a range of gt_zero.  However, if the "gt_zero" parameter is NaN,
the actual result will be the "lt_zero" parameter.

This analysis depends on the is_a_number analysis also added in this MR.
Assuming this doesn't cause any unforeseen problems, I believe we should
wait a bit, then nominate a subset of the series for the stable
branches.

This fixes the piglit tests

    tests/spec/glsl-1.30/execution/range_analysis_fmax_of_nan.shader_test
    tests/spec/glsl-1.30/execution/range_analysis_fmin_of_nan.shader_test

from https://gitlab.freedesktop.org/mesa/piglit/-/merge_requests/463.

Even with the added fsat fixes, range_analysis_fsat_of_nan.shader_test
still fails.  There are some other issues there that will be addressed
in later commits (in another MR).

v2: Add fsat fixes.  Suggested by Rhys.

Fixes: 405de7ccb6c ("nir/range-analysis: Rudimentary value range analysis pass")
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Shader-db results:

All Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 21049290 -> 21049314 (<.01%)
instructions in affected programs: 3175 -> 3199 (0.76%)
helped: 0
HURT: 17
HURT stats (abs)   min: 1 max: 3 x̄: 1.41 x̃: 1
HURT stats (rel)   min: 0.20% max: 1.89% x̄: 0.97% x̃: 0.92%
95% mean confidence interval for instructions value: 1.09 1.73
95% mean confidence interval for instructions %-change: 0.75% 1.19%
Instructions are HURT.

total cycles in shared programs: 855136176 -> 855136406 (<.01%)
cycles in affected programs: 37579 -> 37809 (0.61%)
helped: 0
HURT: 17
HURT stats (abs)   min: 12 max: 20 x̄: 13.53 x̃: 14
HURT stats (rel)   min: 0.17% max: 1.13% x̄: 0.79% x̃: 0.91%
95% mean confidence interval for cycles value: 12.53 14.53
95% mean confidence interval for cycles %-change: 0.63% 0.94%
Cycles are HURT.

Fossil-db results:

Tiger Lake
Instructions in all programs: 160901033 -> 160902591 (+0.0%)
SENDs in all programs: 6812270 -> 6812270 (+0.0%)
Loops in all programs: 38225 -> 38225 (+0.0%)
Cycles in all programs: 7430016795 -> 7429003266 (-0.0%)
Spills in all programs: 192582 -> 192582 (+0.0%)
Fills in all programs: 304539 -> 304539 (+0.0%)

Ice Lake
Instructions in all programs: 145299102 -> 145301634 (+0.0%)
SENDs in all programs: 6863890 -> 6863890 (+0.0%)
Loops in all programs: 38219 -> 38219 (+0.0%)
Cycles in all programs: 8798390846 -> 8798589772 (+0.0%)
Spills in all programs: 216880 -> 216880 (+0.0%)
Fills in all programs: 334250 -> 334250 (+0.0%)

Skylake
Instructions in all programs: 135889478 -> 135892010 (+0.0%)
SENDs in all programs: 6802916 -> 6802916 (+0.0%)
Loops in all programs: 38216 -> 38216 (+0.0%)
Cycles in all programs: 8442624166 -> 8442597324 (-0.0%)
Spills in all programs: 194839 -> 194839 (+0.0%)
Fills in all programs: 301116 -> 301116 (+0.0%)

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9108>