Revert "Build Qt for OS X and iOS with relative rpath"

The change was made too late in the 5.4.0 release
cycle, and broke the Qt build and deployment in
several areas:
	- macdeployqt
	- OS X 10.7 builds
	- shadow builds

This reverts commit c0a54efc

.

Change-Id: I1c1ad4901228f5516352ccdfa963e8ea2b5013b6
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@theqtcompany.com>