The strategy to generate this file was changed. Until now, Linuxconf
was proposing the update the sendmail.cf file if it was not matching
the proposed configuration. this was handy for those relying only
on Linuxconf for sendmail configuration, but not so fun for the other:
They had no option other than not using mailconf at all.
The new strategy is slightly changed: If sendmail.cf was generated
by Linuxconf, then the previous strategy apply. If it was not (or was
modified, even just a byte), then Linuxconf won't take about it. The
only way to get a new sendmail.cf from Linuxconf will be interactive
when changing configuration in mailconf itself.