Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.Approved by: re (implicit)Sponsored by: The FreeBSD Foundation
MFH (r254407, r254960, r255371): misc cleanupMFH (r255386): make libssh privateMFH (r255369, r255376, r255393, r262530): import OpenPAM Nummularia
MFV (r255364): move the code around in preparation for Nummularia.
Prepare for OpenPAM Nummularia by reorganizing to match its new directorystructure.
Vendor import of OpenPAM Micrampelis.
Merge upstream r509: don't log an error in the common case (ENOENT).
Vendor import of OpenPAM Lycopsida.