radeonsi/nir: Don't lower constant arrays to uniforms

shader-db results:

Totals:
SGPRS: 3955968 -> 3954960 (-0.03 %)
VGPRS: 2220220 -> 2220092 (-0.01 %)
Spilled SGPRs: 11387 -> 11325 (-0.54 %)
Spilled VGPRs: 97 -> 97 (0.00 %)
Private memory VGPRs: 2528 -> 2528 (0.00 %)
Scratch size: 2656 -> 2656 (0.00 %) dwords per thread
Code Size: 76002204 -> 75994988 (-0.01 %) bytes
LDS: 740 -> 740 (0.00 %) blocks
Max Waves: 772776 -> 772787 (0.00 %)
Wait states: 0 -> 0 (0.00 %)

Totals from affected shaders:
SGPRS: 16840 -> 15832 (-5.99 %)
VGPRS: 16452 -> 16324 (-0.78 %)
Spilled SGPRs: 1416 -> 1354 (-4.38 %)
Spilled VGPRs: 0 -> 0 (0.00 %)
Private memory VGPRs: 2016 -> 2016 (0.00 %)
Scratch size: 2040 -> 2040 (0.00 %) dwords per thread
Code Size: 953624 -> 946408 (-0.76 %) bytes
LDS: 303 -> 303 (0.00 %) blocks
Max Waves: 1622 -> 1633 (0.68 %)
Wait states: 0 -> 0 (0.00 %)

There were a large number of regressions in code size, but they seem to
be because NIR unrolls some loop which results in the table being
replaced by a bunch of immediates on multiplies etc. -- this bloats code
size since the table size is now included, but means that there are less
loads so it's still a net positive.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
22 jobs for !1873 with review/gallium-disable-glsl-const in 35 minutes and 14 seconds (queued for 19 seconds)
latest detached
Status Job ID Name Coverage
  Containers Build
passed #571856
debian

00:00:24

 
  Build+Test
passed #571865
meson-arm64

00:01:32

passed #571864
meson-armhf

00:02:11

passed #571859
meson-clang

00:09:34

passed #571862
meson-clover

00:10:54

passed #571866
meson-i386

00:04:35

passed #571857
meson-main

00:11:45

passed #571858
meson-swr-glvnd

00:07:03

passed #571863
meson-vulkan

00:01:57

passed #571868
scons-llvm

00:04:55

passed #571867
scons-nollvm

00:02:31

passed #571860
scons-swr

00:07:14

passed #571861
scons-win64

00:07:56

 
  Test
passed #571869
test-llvmpipe-gles2 1/4

00:03:46

passed #571870
test-llvmpipe-gles2 2/4

00:04:00

passed #571871
test-llvmpipe-gles2 3/4

00:03:33

passed #571872
test-llvmpipe-gles2 4/4

00:03:53

passed #571873
test-softpipe-gles2 1/4

00:01:40

passed #571874
test-softpipe-gles2 2/4

00:01:35

passed #571875
test-softpipe-gles2 3/4

00:01:45

passed #571876
test-softpipe-gles2 4/4

00:01:35

passed #571877
test-softpipe-gles3-limited

00:05:24