Libport.Foreach: stop working around MacPorts.
Libport.Foreach: stop working around MacPorts.

See https://trac.macports.org/ticket/32558, the workaround was removed.

	* include/libport/foreach.hh: MacPorts' Boost 1.48 is a regular
	Boost again.

aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport