Disable libxpm under bionic
Disable libxpm under bionic

We recently starting building binaries are part of
the libxpm build, but binaries built with libX11
currently don't link under bionic due to undefined
symboles (e.g. creat).

TBR=bradnelson

Review URL: https://codereview.chromium.org/946743002

Schibum/naclports,yeyus/naclports,yeyus/naclports,yeyus/naclports,Schibum/naclports,yeyus/naclports,yeyus/naclports,Schibum/naclports,Schibum/naclports,Schibum/naclports,yeyus/naclports,Schibum/naclports