Fix: Fluidsynth should not try to lock sample data in memory

[nielsmh]

This should avoid warnings about memory locking from Fluidsynth:
fluidsynth: warning: Failed to pin the sample data to RAM; swapping is possible.

[PeterN]

src/music/fluidsynth.cpp:66:24: error: use of undeclared identifier 'settings'
fluid_settings_setint(settings, "synth.lock-memory", 0);

[PeterN]

This does not solve the problem for me. Checking the return value of fluid_settings_setint gives a failed response, but I can't see a reason.

[nielsmh]

I'm not sure if moving the setint call up actually solves it, but it is probably more correct.

[PeterN]

It does not, I had already tried this.

[nielsmh]

Tested this on my own Fedora 29 system with fluidsynth 1.1.11, and this patch does solve the Failed to pin sample data warning.

[PeterN]

Still does not work for me, but if it works for you, that's good.