MIPS optimizations for AECM audio processing module

R=andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2279005

Patch from Ljubomir Papuga <lpapuga@mips.com>.

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5110 4adac7df-926f-26a2-2b94-8c16560cd09d
5 files changed