Update hhvm config for 3.3

The 3.3+ HHVM packages have changed some file locations. In addition to
the path changes, sync /etc/hhvm/php.ini configuration settings with
operations/puppet.git.

See also: Id032f68a3b31f1339c798295f82f9e3d5d519bfe
Bug: 71274
Change-Id: I17173cc461f667e146bf8c8ed2a8bc2b21c6045e