nir/spirv: don't use bare types, remove assert in split vars for testing
For OpenCL we never want to strip the info from the types, and it makes type comparisons easier in later stages. We might later need a nir pass to strip this for GLSL, but so far the only regression is the assert and Jason said removing that is fine.
Signed-off-by: Dave Airlie airlied@redhat.com