[VIM] OpenBSD mbuf issue upgraded to "security"

[Steven M. Christey]

Ref: SECTRACK:1017735

Thought I'd mention this for the vdb's who don't report reliability
problems.

Issue was originally reported by OpenBSD as a RELIABILITY FIX and
crash, as archived in SECTRACK:1017735, but the errata has since been
changed/upgraded to security fix.

Reference: http://www.openbsd.org/errata39.html#m_dup1
Reference: http://www.openbsd.org/errata40.html#m_dup1

This is CVE-2007-1365

- Steve