GLSL: Don't apply Grad LOD workarounds for fetch.
GLSL: Don't apply Grad LOD workarounds for fetch.

KhronosGroup/SPIRV-Cross,KhronosGroup/SPIRV-Cross,KhronosGroup/SPIRV-Cross,KhronosGroup/SPIRV-Cross,KhronosGroup/SPIRV-Cross,KhronosGroup/SPIRV-Cross