Do not emit hoisted access chain temporaries unless backend supports it.
Do not emit hoisted access chain temporaries unless backend supports it.

This can happen for access chains into buffer objects which were marked
as potentially hoisted, but it's benign in almost all cases.

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