Previously, `CMAKE_ASM${DIALECT}_COMPILER_FRONTEND_VARIANT` and
`CMAKE_ASM${DIALECT}_SIMULATE_ID` were not saved in with the build
configuration. As a result, these were left unpopulated on re-configure.
This is particularly problematic when `clang-cl` is used as the
assembler on Windows, since CMake would mistakenly identify the build as
being "GCC on Windows", resulting in include paths being passed with
forward slashes on re-configure, causing a full rebuild.
Fix the issue by saving the information so it persists across
re-configures.
Fabrice de Gans
d75d5dfadf