games/coffeebreak: Correct sed and patch applied twice

Last commit "Move man to share/man" I used patch to set MANDIR and sed
to fix hardcoded PREFIX=/usr/local on wrksrc Makefile.

Simplify and correct changes with use of MAKE_ARGS.
Not bumping port revision as is doesn't change build.

Reported by: danfe
Approved by: portmgr (blanket)
Fixes: 021fcd36af22 Move man pages to share/man