Cleanup/wg init (#260)

* remove wg_init and wg_finalize from functional tests

* Remove wg_init and wg_finalize from examples

* deprecate wg_init/finalize

* Updated docs

* Typo in documentation

---------

Co-authored-by: Yiltan <yiltan@amd.com>

[ROCm/rocshmem commit: 6e7277b544]

projects/rocshmem/tests/functional_tests/sync_all_tester.cpp

@@ -39,7 +39,6 @@ __global__ void SyncAllTest(int loop, int skip, long long int *start_time,
   int wg_id = get_flat_grid_id();
   int wf_id = t_id / wf_size;
 
-  rocshmem_wg_init();
 
   for (int i = 0; i < loop + skip; i++) {
     if (hipThreadIdx_x == 0 && i == skip) {
@@ -84,7 +83,6 @@ __global__ void SyncAllTest(int loop, int skip, long long int *start_time,
     end_time[wg_id] = wall_clock64();
   }
 
-  rocshmem_wg_finalize();
 }
 
 /******************************************************************************