hhvm: Update to dynamic extension path
hhvm: Update to dynamic extension path

Updated dynamic_extension_path in php.ini to reflect ABI in the latest
hhvm package.

Change-Id: I8da47ba645d3618101d7ebf796f0146c05f17854

stuartbman/mediawiki-vagrant,stuartbman/mediawiki-vagrant,ankita-kumari/mediawiki-vagrant,HarriAlasi/wiki3dviewer,ankita-kumari/mediawiki-vagrant,ankita-kumari/mediawiki-vagrant,wikimedia/mediawiki-vagrant,stuartbman/mediawiki-vagrant,stuartbman/mediawiki-vagrant,HarriAlasi/wiki3dviewer,stuartbman/mediawiki-vagrant,wikimedia/mediawiki-vagrant,HarriAlasi/wiki3dviewer,wikimedia/mediawiki-vagrant,HarriAlasi/wiki3dviewer,ankita-kumari/mediawiki-vagrant,ankita-kumari/mediawiki-vagrant,HarriAlasi/wiki3dviewer,wikimedia/mediawiki-vagrant,HarriAlasi/wiki3dviewer,wikimedia/mediawiki-vagrant,wikimedia/mediawiki-vagrant,ankita-kumari/mediawiki-vagrant,stuartbman/mediawiki-vagrant,HarriAlasi/wiki3dviewer,stuartbman/mediawiki-vagrant