Remove libmodplug from the list of prebuild ports.
Remove libmodplug from the list of prebuild ports.

I'm not sure why this library was ever in this
list.  No packages currently depend on it.

Its currently breaking the SDL naclports bot
since it recently became dependant on glibc-compat
which we is not part of sdk-libs.

R=binji@chromium.org

Review URL: https://codereview.chromium.org/611273003

yeyus/naclports,kuscsik/naclports,dtkav/naclports,kuscsik/naclports,yeyus/naclports,kuscsik/naclports,Schibum/naclports,Schibum/naclports,dtkav/naclports,Schibum/naclports,yeyus/naclports,Schibum/naclports,dtkav/naclports,dtkav/naclports,kuscsik/naclports,kuscsik/naclports,yeyus/naclports,Schibum/naclports,yeyus/naclports,yeyus/naclports,dtkav/naclports,Schibum/naclports