SWDEV-1 - Add EMU_ENV option

Fix FEAT-39125
Add EMU_ENV option. If it is ON, the building is for
emulation environment, thus some logics can be adjusted
to match emulation environment. If it is OFF, the
building is for regular environment.
Currently only ocltst will use the option. But it can
be used for other modules.

Change-Id: I54e1bc1309e82794b41fca2ae1f01f004138dced


[ROCm/clr commit: 76c6dcd558]

projects/clr/opencl/tests/ocltst/module/runtime/OCLAsyncMap.cpp

@@ -27,8 +27,14 @@
 
 #include "CL/cl.h"
 
+#if EMU_ENV
+static const size_t BufSize = 0x800;
+static const size_t MapRegion = 0x100;
+#else
 static const size_t BufSize = 0x800000;
 static const size_t MapRegion = 0x100000;
+#endif // EMU_ENV
+
 static const unsigned int NumMaps = BufSize / MapRegion;
 
 OCLAsyncMap::OCLAsyncMap() { _numSubTests = 1; }