Add a message to genimage about bus messages

The service handling in systemd causes it to show scary
looking messages to user.  This reassures that the message
is benign.

xCAT-server/share/xcat/netboot/sles/genimage

@@ -957,6 +957,7 @@ if ($dracutmode) {
     push @ndrivers, @drivers;
     mkinitrd("stateless");
 }
+print "It is safe to ignore message 'Failed to connect to bus: No such file or directory' that may have appeared above one or more times.\n";
 
 sub getlibs {
     my $file    = shift;