spirv: Silence a bunch of unused parameter warnings

spirv: Silence a bunch of unused parameter warnings

The change to get_uniform_nir_atomic_op make it look like the other
get_*_nir_atomic_op functions.  The rest just add UNUSED or ASSERTED
to parameters required for some of the interfaces.

src/compiler/spirv/spirv_to_nir.c: In function ‘struct_member_decoration_cb’:
src/compiler/spirv/spirv_to_nir.c:673:47: warning: unused parameter ‘val’ [-Wunused-parameter]
                             struct vtn_value *val, int member,
                                               ^~~
src/compiler/spirv/spirv_to_nir.c: In function ‘struct_member_matrix_stride_cb’:
src/compiler/spirv/spirv_to_nir.c:778:50: warning: unused parameter ‘val’ [-Wunused-parameter]
                                struct vtn_value *val, int member,
                                                  ^~~
src/compiler/spirv/spirv_to_nir.c: In function ‘type_decoration_cb’:
src/compiler/spirv/spirv_to_nir.c:805:61: warning: unused parameter ‘ctx’ [-Wunused-parameter]
                     const struct vtn_decoration *dec, void *ctx)
                                                             ^~~
src/compiler/spirv/spirv_to_nir.c: In function ‘spec_constant_decoration_cb’:
src/compiler/spirv/spirv_to_nir.c:1359:70: warning: unused parameter ‘v’ [-Wunused-parameter]
 spec_constant_decoration_cb(struct vtn_builder *b, struct vtn_value *v,
                                                                      ^
src/compiler/spirv/spirv_to_nir.c: In function ‘handle_workgroup_size_decoration_cb’:
src/compiler/spirv/spirv_to_nir.c:1407:43: warning: unused parameter ‘data’ [-Wunused-parameter]
                                     void *data)
                                           ^~~~
src/compiler/spirv/spirv_to_nir.c: In function ‘vtn_handle_function_call’:
src/compiler/spirv/spirv_to_nir.c:1806:55: warning: unused parameter ‘opcode’ [-Wunused-parameter]
 vtn_handle_function_call(struct vtn_builder *b, SpvOp opcode,
                                                       ^~~~~~
src/compiler/spirv/spirv_to_nir.c:1807:54: warning: unused parameter ‘count’ [-Wunused-parameter]
                          const uint32_t *w, unsigned count)
                                                      ^~~~~
src/compiler/spirv/spirv_to_nir.c: In function ‘get_uniform_nir_atomic_op’:
src/compiler/spirv/spirv_to_nir.c:2548:47: warning: unused parameter ‘b’ [-Wunused-parameter]
 get_uniform_nir_atomic_op(struct vtn_builder *b, SpvOp opcode)
                                               ^
src/compiler/spirv/spirv_to_nir.c: In function ‘vtn_handle_atomics’:
src/compiler/spirv/spirv_to_nir.c:2633:48: warning: unused parameter ‘count’ [-Wunused-parameter]
                    const uint32_t *w, unsigned count)
                                                ^~~~~
src/compiler/spirv/spirv_to_nir.c: In function ‘vtn_handle_barrier’:
src/compiler/spirv/spirv_to_nir.c:3197:48: warning: unused parameter ‘count’ [-Wunused-parameter]
                    const uint32_t *w, unsigned count)
                                                ^~~~~
src/compiler/spirv/spirv_to_nir.c: In function ‘vtn_handle_execution_mode’:
src/compiler/spirv/spirv_to_nir.c:3618:68: warning: unused parameter ‘data’ [-Wunused-parameter]
                           const struct vtn_decoration *mode, void *data)
                                                                    ^~~~

Acked-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/767>