[DO NOT MERGE] ch4/ucx: Support GPU buffers as window memory

Recent versions of UCX handle this case correctly.

src/mpid/ch4/netmod/ucx/ucx_win.c

@@ -48,14 +48,7 @@ static int win_allgather(MPIR_Win * win, size_t length, uint32_t disp_unit, void
 
  MPIDI_UCX_WIN(win).mem_mapped = false;
 
- /* As of ucx-1.10, mapping with a CUDA device buffer may be successful but
- * later RMA segfaults inside UCX. Thus, MPICH manually disables native RMA for device win buffer for now.*/
- if (MPIR_GPU_query_pointer_is_dev(*base_ptr)) {
- status = UCS_ERR_UNSUPPORTED;
- } else {
- status = ucp_mem_map(MPIDI_UCX_global.context, &mem_map_params, &mem_h);
- }
-
+ status = ucp_mem_map(MPIDI_UCX_global.context, &mem_map_params, &mem_h);
  /* some memory types cannot be mapped, skip rkey packing */
  if (status != UCS_ERR_UNSUPPORTED) {
  MPIDI_UCX_CHK_STATUS(status);