kfdtest: MigrateFileBackedRangeTest address sanitizer builds failing

Use alloca to replace variable size array.



Change-Id: I81e5a7d8f6ace203b81f5f5a651b2a6aa948821c
Signed-off-by: Philip Yang <Philip.Yang@amd.com>


[ROCm/ROCR-Runtime commit: 88e6921d45]

projects/rocr-runtime/tests/kfdtest/src/KFDSVMRangeTest.cpp

@@ -1226,7 +1226,8 @@ TEST_F(KFDSVMRangeTest, MigrateFileBackedRangeTest) {
     ASSERT_NE(-1, fd);
 
     size_t size = PAGE_SIZE;
-    char buf[size] = {0x30};
+    char *buf = reinterpret_cast<char *>(alloca(size));
+    memset(buf, 0x30, size);
 
     ASSERT_EQ(size, write(fd, buf, size));