Fix generate_asm_header.

In gyp, "inputs" always takes path relative to the gyp file.
The path in "action" is absolute since it can be included from a different directory.
Review URL: https://webrtc-codereview.appspot.com/965026

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@3100 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed