added active message example
added active message example

sergsagal1/ucx_rocm,manjugv/ucx,miked-mellanox/ucx,sergsagal1/ucx_rocm,miked-mellanox/ucx,biddisco/ucx,shssf/ucx,abouteiller/ucx,miked-mellanox/ucx,manjugv/ucx,abouteiller/ucx,biddisco/ucx,biddisco/ucx,abouteiller/ucx,shssf/ucx,shssf/ucx,manjugv/ucx,abouteiller/ucx,sergsagal1/ucx_rocm