[tlbuild] freetype2 library built in objs/.libs but xetex looks in libs

[Ed Avis]

Building texlive-20080816-source fails because

make[2]: *** No rule to make target 
`../../libs/freetype2/.libs/libfreetype.a', needed by `xetex'.  Stop.
make[2]: Leaving directory 
`/home/ed/inst/texlive-20080816-source/texk/web2c'

A file libfreetype2.a has been built, but it lives in 
libs/freetype2/objs/.libs instead of libs/freetype2/.libs.  Adding a 
symlink lets the build get past this error.

-- 
Ed Avis <ed at membled.com>