adjust missing NO_PACKING and MODPLUG_NO_FILESAVE ifdefs:

[sezero]

CSoundFile::PackSample() and CSoundFile::CanPackSample() are only
used when writing samples and only when NO_PACKING is not defined.
sample write, in turn, is only available when MODPLUG_NO_FILESAVE
is not defined. therefore, wrap them with MODPLUG_NO_PACKING and
NO_FILESAVE ifdefs in sndfile.h, and move the MODPLUG_NO_PACKING
ifdef in sndfile.cpp to cover PackSample() and CanPackSample() too.
This doesn't affect the C-only interface, however CSoundFile class
in the C++ interface is changed, therefore MODPLUG_LIBRARY_VERSION
in configure.ac would probably need changing before a release.

[Konstanty]

Currently I don't like the idea of changing the interface for no "good" reason. The features before/after are the same.

[sagamusix]

Any code that has to do with NO_PACKING should be removed anyway - There's no reason to still support writing ModPlug-style ADPCM sample hacks into files these days.

[sezero]

Any code that has to do with NO_PACKING should be removed anyway -
There's no reason to still support writing ModPlug-style ADPCM sample
hacks into files these days.

I agree, but he doesn't want to change the api unless there are new features.

Apart form this, I disabled the midi and wav formats loading in my fork
(configurable using new defines), but that would be unacceptable too I
think, so I'm keeping that to myself.

[sagamusix]

Yes, the API shouldn't be changed (libmodplug did this before when increasing the minor version and that is a very bad thing to do), but at least the code for this could be removed, so that it's impossible to create ADPCM-compressed samples.

[sezero]

This PR is stale. Closing.