gallium/ntt: lower uniforms to ubo
NTT doesn't handle uniforms, and requires them to have been lowered to UBOs. But for drivers that don't set nir_shader_compiler_options::lower_uniforms_to_ubo to true, this won't have happened yet. Neither Zink nor V3D sets this option, and in the case of Zink this isn't trivial to change.
So let's lower uniforms to UBOs in this case in NTT instead.
Fixes: 03c60762 ("gallium/ntt: Fix load_ubo_vec4 buffer index setup.") Closes: #4047 (closed)