configure.ac : Relax automake version requirements.
configure.ac : Relax automake version requirements.

Suggested-by: Jan Stary <8800578b51f022c8d8adb9606a8b3db4fedbdac6@stare.cz>

waitman/flac,waitman/flac,waitman/flac,waitman/flac,waitman/flac