Fix multiple vulnerabilities in file(1) and libmagic(3).

Security:	FreeBSD-SA-14:28.file
Security:	CVE-2014-3710, CVE-2014-8116, CVE-2014-8117
Approved by:	so


git-svn-id: svn+ssh://svn.freebsd.org/base/releng/10.0@275671 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f