spirv: add missing non-uniform access for SSBO atomics

This fixes new VKCTS coverage
dEQP-VK.descriptor_indexing.non_uniform_atomics.

Found this while implementing a new extension.

Cc: mesa-stable
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37295>

src/compiler/spirv/spirv_to_nir.c

@@ -4524,6 +4524,8 @@ vtn_handle_atomics(struct vtn_builder *b, SpvOp opcode,
 
       if (ptr->mode != vtn_variable_mode_workgroup)
          access |= ACCESS_COHERENT;
+      if (ptr->access & ACCESS_NON_UNIFORM)
+         access |= ACCESS_NON_UNIFORM;
 
       nir_intrinsic_set_access(atomic, access);