kfdtest: Add RDMATest ContiguousVRAMAllocation

Update amdp2ptest.h to sync with the same file from rdma test driver
folder.

Add ContiguousVRAMAllocation to verify rdma get pages will get
contiguous VRAM pages, skipped RDMA getpages if amdp2ptest.ko is not
loaded.

Change rdma buffer mmap with MAP_SHARED flag, because MAP_PRIVATE goes
to COW path, which requires mmap the entire vma and cannot support
multiple sg nents.

Change-Id: I5fbb1902251f1454616d4404a4b048a88996d4f7
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Signed-off-by: Chris Freehill <cfreehil@amd.com>


[ROCm/ROCR-Runtime commit: e076a4ee82]

projects/rocr-runtime/libhsakmt/tests/kfdtest/src/RDMAUtil.cpp

@@ -60,7 +60,7 @@ void *LocalMemoryAccess::MMap(uint64_t offset, size_t size) {
     if (fd <= 0)
         return NULL;
 
-    gpuAddr = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, offset);
+    gpuAddr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, offset);
     return gpuAddr;
 }