games/seabattle: update to 1.1 and unbreak on FreeBSD 13+

After having sent a number of FreeBSD patches to the author, he
updated the project and incorporated them. So this is mainly a
patch release.

Port changes:

• remove patches incorporated by upstream
• unbreak build on FreeBSD 13+
• set LICENSE to MIT
• depend on audio/alsa-utils if audio output is desired
• take up maintainership of this unmaintained port

PR: 260633
Reported by: Robert Clausecker <fuz@fuz.su> (new maintainer)