Shader arrays are currently restricted to 64K entries for all translator
back ends.   This is being changed to just HLSL, since the other back
ends appear to have support for larger sizes.

Bug: angleproject:3865
Test: dEQP-GLES31.functional.compute.basic.copy_image_to_ssbo_large
Test: dEQP-GLES31.functional.compute.basic.copy_ssbo_to_image_large
Test: ComputeShaderTest.VeryLargeArrayInsideFunction/*
Change-Id: I9a9d1322e24b3206debdea6a3fd517b4d6869ed9
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1821943
Commit-Queue: Tim Van Patten <timvp@google.com>
Reviewed-by: Tobin Ehlis <tobine@google.com>