* Harness: Added an option for a test to skip itself.
New condtion in callSingleTestFunction. This allows a test to return TEST_SKIP if the device does not support the requested test.
* Split generic_ptr_to_host_mem into two tests.
The old generic_ptr_to_host_mem test tests two different device capabilities (SVM and not SVM). This is a prerequisite for the following commit.
* Generic Address Space: Skip tests utlilising SVM on devices that do not support SVM.
Where a device does not support SVM, do not run the generic address space test(s) that rely on SVM.
