Allow to build with the PyPI package "clang" instead of "libclang". 1. It seems to be maintained. 2. In the FreeBSD base system there is no pre-built libclang.so. If you need this library you have to install llvm from ports additionally. 2. On FreeBSD there is no pre-built wheel "libclang" with a packaged libclang.so.

# CMake toolchain file, cf. README.mingw_cross
SET(CMAKE_SYSTEM_NAME Windows)
include(CMakeForceCompiler)
IF("${GNU_HOST}" STREQUAL "")
	SET(GNU_HOST i586-mingw32msvc)
ENDIF()
# Prefix detection only works with compiler id "GNU"
CMAKE_FORCE_C_COMPILER(${GNU_HOST}-gcc GNU)
SET(CMAKE_RC_COMPILER ${GNU_HOST}-windres)