Triggered by: kris wants to remove broken ports
Approved by: maintainer timeout (he hasn't much time at the moment
and I want to have bugs get reported just in time to
have it fixed before 5.1)
Submitted by: Sven Petai <hadara@bsd.ee>
PR: 34160
also:
Use new FIND and DATADIR macros.
Simplify do-install target.
Add warning.
The csound.txt data file has been renamed upstream to csound.xmg,
so don't rename it to csound.dat. Users will know it is not a text
file.