GitLab

- Update rocshmem submodule to commit with lazy env var reading,
  so ROCSHMEM_HEAP_SIZE set via os.environ can take effect before
  C++ library initialization
- Align num_rdma_bytes to 2GB boundary using bit shifts instead of
  magic numbers
- Update build.sh to checkout the new rocshmem commit
Signed-off-by: lijian <34831075+lijian0711@users.noreply.github.com>