Implement rocshmem_ptr in IPC conduit (#197)

* Implement `rocshmem_ptr` in IPC conduit

* tests: add functional test for `rocshmem_ptr`
  - Add safety check for pointer access and condition check before printing results for `rocshmem_ptr` test
  - Use `rocshmem_put` to store `rocshmem_ptr` availability for data validation

tests/functional_tests/shmem_ptr_tester.hpp

@@ -43,7 +43,7 @@ class ShmemPtrTester : public Tester {
 
   virtual void verifyResults(size_t size) override;
 
-  char *r_buf = nullptr;
+  char *dest = nullptr;
   int *_available = nullptr;
 };