Log Message:
samba4: updated to 4.12.6

Changes since 4.12.5
* BUG 14403: s3: libsmb: Fix SMB2 client rename bug to a Windows server.
* BUG 14424: dsdb: Allow "password hash userPassword schemes = CryptSHA256"
  to work on RHEL7.
* BUG 14450: dbcheck: Allow a dangling forward link outside our known NCs.
* BUG 14426: lib/debug: Set the correct default backend loglevel to
  MAX_DEBUG_LEVEL.
* BUG 14428: PANIC: Assert failed in get_lease_type().
* BUG 14422: util: Fix build on AIX by fixing the order of replace.h include.
* BUG 14355: srvsvc_NetFileEnum asserts with open files.
* BUG 14354: KDC breaks with DES keys still in the database and
  msDS-SupportedEncryptionTypes 31 indicating support for it.
* BUG 14427: s3:smbd: Make sure vfs_ChDir() always sets
  conn->cwd_fsp->fh->fd = AT_FDCWD.
* BUG 14428: PANIC: Assert failed in get_lease_type().
* BUG 14358: docs: Fix documentation for require_membership_of of
  pam_winbind.conf.
* BUG 14444: ctdb-scripts: Use nfsconf utility for variable values in CTDB
  NFS scripts.
* BUG 14425: s3:winbind:idmap_ad: Make failure to get attrnames for schema
  mode fatal.