Since commit 84036d30 (IntelLLVM: Fix C/C++ standard level flags on
Windows, 2021-07-07, v3.21.0-rc3~8^2~1) we activate C/C++ standard level
logic for IntelLLVM when targeting the MSVC ABI.  Update the
`RunCMake.try_compile` test to be aware of this even when CMake is
itself configured by an older CMake that does not know this.