kfdtest: fix a memory leak issue in MMapLarge test

When mapMemoryToGpu fails, we need unregister it with user address as
the gpu address is not available.

Change-Id: I4418eeaa7aa37008f5bffa144e2c2171f0d238fd
Signed-off-by: xinhui pan <xinhui.pan@amd.com>

tests/kfdtest/src/KFDMemoryTest.cpp

@@ -168,7 +168,7 @@ TEST_F(KFDMemoryTest, MMapLarge) {
             break;
         if (hsaKmtMapMemoryToGPUNodes(addr + i, s - i,
                     &AlternateVAGPU[i], mapFlags, 1, (HSAuint32 *)&defaultGPUNode)) {
-            hsaKmtDeregisterMemory((void*)AlternateVAGPU[i]);
+            hsaKmtDeregisterMemory(addr + i);
             break;
         }
     }