Revert 6481 and 6482

Revert 6482 "Update webrtc to fix unpack_lib expansion."
Revert 6481 "Update generated asm offsets scripts."

The roll has not been successful. Reverted based on the request of the
committer.


TBR=turaj

Review URL: https://webrtc-codereview.appspot.com/17759004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6495 4adac7df-926f-26a2-2b94-8c16560cd09d