[Fontconfig] build notes for fontconfig

[Eric Lenio]

When building fontconfig on my system like this:

  ./configure \
      --prefix=/opt/sw \
      --with-confdir=/opt/sw/etc/fonts \
      --x-libraries=/opt/xfree86/current/lib \
      --x-includes=/opt/xfree86/current/include \
      --with-expat-includes=/opt/sw/include \
      --with-expat-lib=/opt/sw/lib \
      --with-freetype-includes=/opt/xfree86/current/include/freetype2 \
      --with-freetype-lib=/opt/xfree86/current/lib \
      --cache-file=/dev/null

the main stuff in src compiles ok but then fc-cache and fc-list both fail to
compile saying that they can't find the libraries for expat and freetype -
looks as if the library locations I specify in configure are not getting passed
into the make process for those subdirs.  Just thought you should know.