Sometimes, the machine file can include compiler command line options,
in order to pick the correct multilib. For example, Meson uses "$cc
--print-search-dirs" to find the library search path, where $cc is the
cc from the machine file. Because the outputs of "gcc -m32
--print-search-dirs" and "gcc --print-search-dirs" are different, this
only works if you have
[binaries]
cc = ['gcc', '-m32']
in the machine file. Right now, however, the cmake module assumes that
the compiler listed in the machine file is either a compiler, or a
"launcher" followed by the compiler. Check if the second argument
starts with a slash (for Microsoft-like compilers) or a dash (for
everyone else), and if so presume that the CMAKE_*_COMPILER_LAUNCHER
need not be defined.