Second iteration of sftp-server -m documentation (#1862504)

openssh-6.7p1-sftp-force-permission.patch

@@ -9,15 +9,16 @@ diff -up openssh-7.2p2/sftp-server.8.sftp-force-mode openssh-7.2p2/sftp-server.8
  .Ek
  .Nm
  .Fl Q Ar protocol_feature
-@@ -138,6 +139,11 @@ Sets an explicit
+@@ -138,6 +139,12 @@ Sets an explicit
  .Xr umask 2
  to be applied to newly-created files and directories, instead of the
  user's default mask.
 +.It Fl m Ar force_file_perms
 +Sets explicit file permissions to be applied to newly-created files instead
 +of the default or client requested mode.  Numeric values include:
-+777, 755, 750, 666, 644, 640, etc.  The umask is not used for uploaded files
-+ if -m is set, but it is still applied on directories.
++777, 755, 750, 666, 644, 640, etc.  Using both -m and -u switches makes the
++umask (-u) effective only for newly created directories and explicit mode (-m)
++for newly created files.
  .El
  .Pp
  On some systems,