- Revert: 0fadbc56461678413851ab1a1784b854839f22b1

This reverts commit 0fadbc56461678413851ab1a1784b854839f22b1
 - extensions may be arch dependent binaries, so their place is in libdir

The arch-dependant symlink is a pain and totally confuses rpm wrt
noarch packages and directory dependencies. Keeping possible arch
dependant binaries in _datadir seems less of a problem.