1. The imported target properties may not contain -D switches in the
INTERFACE_COMPILE_DEFINITIONS property, because CMake will always
prepend them to each item. Therefore we have to remove those switches
and also pass other options (e.g. -fexceptions) in INTERFACE_COMPILE_OPTIONS
property, otherwise CMake creates "mutants" '-D-fexceptions' alike.
2. FindOpenSSL.cmake variable for include directory is
OPENSSL_INCLUDE_DIR, not OPENSSL_INCLUDE_DIRS.
`PC_LIBTORRENT_RASTERBAR_CFLAGS` not only gives you the definitions, but
also includes the include path flags (`-I...`).
This causes problesm when passing the result to
`target_compile_definitions`. The resulting compiler command would then
look something like this:
/usr/bin/c++ -D-I/home/...
This change uses `PC_LIBTORRENT_RASTERBAR_CFLAGS_OTHER` instead which
does not contain the include path flags.
Eugene Shalygin