cl20: api:  Allow vendor flags (#666)
cl20: api:  Allow vendor flags (#666)

Mask off vendor extensions when querying host command queue properties.

Khronos Bug: https://github.com/KhronosGroup/OpenCL-CTS/issues/642
Test Suite Affected: api
KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS