Obtain a credential on login with KDM4

PAM_SETCRED(3)'s second parameter does not default to PAM_ESTABLISH_CRED on
FreeBSD, so explify it, as was proposed on the forums[1] back in decembre.

Bump port revision as this commit changes the runtime behavior of the
installed port.

[1] https://forums.freebsd.org/threads/problem-with-kdm4-kerberos-and-nfsv4.49253

PR: 195899
Approved by: rakuco (mentor)
MFH: 2015Q1