iosdeviceinfo.cc: remove unnecessary file

The do-nothing implementation in this file is already present in
mobiledevicemanager.cc (shared with Android) so this isn't adding value, and
causes duplicate-symbol errors under some compilers.

BUG=3201
R=henrike@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/11959004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/talk@5899 4adac7df-926f-26a2-2b94-8c16560cd09d
2 files changed