MFH: r385792

Add a patch to fix the HWP filter vulnerability documented in
CVE-2015-1774 and
http://www.openoffice.org/security/cves/CVE-2015-1774.html

Approved by: ports-secteam (erwin)
Security: b13af778-f4fc-11e4-a95d-ac9e174be3af
Differential Revision: https://reviews.freebsd.org/D2478