Refactor RO backend data structures (#49)

- Remove hdp and ipc pointers from BlockHandle, align RO stats with RO contexts

- Add run commands for `rocshmem_g` and `rocshmem_p` API tests in driver.sh

- Allocate rocshmem API return buffers based on number of device contexts.

- Associate status flag address with blocking calls and remove threadId dependency
   - Associated the status flag address with each blocking call request to notify the GPU thread.
   - Removed dependency on threadId for determining the appropriate status flag index.

- Move status flag buffer allocation to backend.

- Initialize allocated memeory to zero

[ROCm/rocshmem commit: df4ad2c04d]

projects/rocshmem/scripts/functional_tests/driver.sh

@@ -179,6 +179,20 @@ TestRMA() {
 
   ExecTest  "teamctxget"       2       1            1         1048576
 
+  ExecTest  "g"                2       1            1         1048576
+  ExecTest  "g"                2       1            1024      512
+  ExecTest  "g"                2       8            1         1048576
+  ExecTest  "g"                2       16           128       8
+  ExecTest  "g"                2       32           256       512
+  ExecTest  "g"                2       64           1024      8
+
+  ExecTest  "p"                2       1            1         1048576
+  ExecTest  "p"                2       1            1024      512
+  ExecTest  "p"                2       8            1         1048576
+  ExecTest  "p"                2       16           128       8
+  ExecTest  "p"                2       32           256       512
+  ExecTest  "p"                2       64           1024      8
+
   ################################ Non-Blocking ################################
 
   ExecTest  "putnbi"           2       1            1         1048576