[iOS] WebKit2.framework is unused
https://bugs.webkit.org/show_bug.cgi?id=133424

Reviewed by Anders Carlsson.

* Configurations/WebKit2.xcconfig: Set SKIP_INSTALL to YES when targeting iOS.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169504 268f45cc-cd09-0410-ab3c-d52691b4dbfc