Adjust the passing value for GPU agent when do max single allocation test

For APU asics, the default configuration size of video memory is
relatively small, while the reserved region becomes larger in recent
generation asics, ratio of max alloc size to the pool size may below
the expected value, so adjust it.

Signed-off-by: Yifan Zhang <yifan1.zhang@amd.com>
Change-Id: I0e847c4c13e957cf6e811d3f379842619cf53370


[ROCm/ROCR-Runtime commit: f05770610c]

projects/rocr-runtime/rocrtst/suites/functional/memory_basic.cc

@@ -233,7 +233,7 @@ void MemoryTest::MaxSingleAllocationTest(hsa_agent_t ag,
   }
 
   if (ag_type == HSA_DEVICE_TYPE_GPU) {
-    EXPECT_GE((float)max_alloc_size/pool_sz, (float)7/8);
+    EXPECT_GE((float)max_alloc_size/pool_sz, (float)3/4);
   }
   if (verbosity() > 0) {
     std::cout << kSubTestSeparator << std::endl;