build-infra: Complement --with-freetype with --with-freetype-lib and --with-freetype-include

In libraries.m4 LIB_SETUP_FREETYPE we setup freetype handling. In contrary to other libraries, it is not possible to point to a separate lib and include directory, with --with-freetype-lib and --with-freetype-include.

This used to be the case but this code got removed some time ago for unclear reasons.

This is actually a regression compared to the old build system where freetype lib and include could be specified separately. Also, it is an incongruency compared to the other libraries in configure.