Draft: server/crypto.c: Use internal debug macro instead of nbdkit_debug function
The convention within the server code is to use the debug macro instead of the nbdkit_debug function. A few places in server/crypto.c didn't do that.
The function and macro are not quite equivalent because the macro checks if 'verbose' is set in the expanded code. (The function checks the flag again.) The difference is not relevant here.
Updates: commit fab4a090