spirv: Do more complex unwrapping in get_nir_type

The OpenGL flavor of SPIR-V allows for samplers inside structs.  This
means that our simple array-of-array handling isn't sufficient and we
need something substantially more complex for generating NIR types.

Fixes: 14a12b771d0 "spirv: Rework our handling of images and samplers"
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6065>
1 file changed