Use the correct prefix for pear on FreeBSD
Use the correct prefix for pear on FreeBSD

As of 2018-03-08, pear is flavored/prefixed in FreeBSD[1]. Remove the
special handling and use the configured prefix as for most other
distributions.

[1] See UPDATING note e.g. on https://www.freshports.org/devel/pear/

mayflower/puppet-php,mayflower/puppet-php