freedreno: Fix the uniform/nonuniform handling for cat5 bindful modes.

We can see from the dynamically_uniform (compiler doesn't know if you're uniform or not) vs uniform (compiler can see it's uniform) case in the blob which is which. Now that we have the right names, also use the nonunif flag for encoding the actual non-uniform mode (previously, we were always setting it always in a way that meant uniform).

I verified this behavior back to a418 with samplers. The a3xx blob I have only does GLES3, so we don't have the opaque_type_indexing tests to see.