Fix ffmpeg build now that get/setrlimit are in libnacl
Fix ffmpeg build now that get/setrlimit are in libnacl

setrlimit is not being detected by ffmpeg but the
RLIMIT_CPU is not present in newlib without
glibc-compat headers.

Review URL: https://codereview.chromium.org/705773004

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