d/rules: Call dh_xx --remaining-packages when using -p

Commit 15104c3c ("d/control: Bump debhelper compat to 12") added
some extra dh overrides specific to certain packages using the "-p"
option, but forgot to add the "dh_xx --remaining-packages" call at the
end. This causes these debhelper commands not to run for the other
packages which introduced some bugs (like missing copyright files).

Add the extra calls to fix this.

Closes: #946373
Thanks: Andreas Beckmann for finding this bug