[build] fix build on Mac after ed000eea
[build] fix build on Mac after ed000eea

The new subdir-objects automake option creates temp files that
trips up the license check. Thanks to Alexander and Noah for
helping to track this down.

fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb