Postfix lookups for catchall case on non-alias domain:
1. user@domain
- virtual_alias_maps.cf -> no match
- virtual_alias_domain_maps.cf -> no match
- virtual_alias_domain_catchall_maps.cf -> no match
- custom virtual_alias_maps -> no match
2. user -> not relevant
3. @domain
- virtual_alias_maps.cf -> **match**, lookup ends here
With an alias domain the behaviour was:
1. user@domain
- virtual_alias_maps.cf -> no match
- virtual_alias_domain_maps.cf -> no match
- virtual_alias_domain_catchall_maps.cf -> **match**, lookup ends here
In this case custom virtual_alias_maps are ignored.
With this change the behaviour is:
1. user@domain
- virtual_alias_maps.cf -> no match
- virtual_alias_domain_maps.cf -> no match
- virtual_alias_domain_catchall_maps.cf -> no match
- custom virtual_alias_maps -> no match
2. user -> not relevant
3. @domain
- virtual_alias_maps.cf -> no match
- virtual_alias_domain_maps.cf -> **match**, lookup ends here
The change removes virtual_alias_domain_catchall_maps.cf entirely and
rewrites virtual_alias_domain_maps.cf to also work for catchall lookups.