debinstall #6825 when distribution is specified in changelog, refuse ldi publish --dist="another distrib" [deprecated]

else one can think everything is ok while it isn't : ldi upload will put packages in the changelog distribution, not the one specified on the command line.

NOTE: another solution is to override the distrib anyway without having to use DISTRIBUTION in the changelog, that would be even better but there may be some drawback unknown to me.