Ignore Program Change Setting is Ignored

[fundamental]

src/Misc/Config.h has a setting named 'IgnoreProgramChange'. A quick git grep of the ZynAddSubFX codebase shows that the value appears to be used within Config.h, Config.cpp, and ConfigUI.fl. Additionally it is present in the zyn-fusion GUI, however it is not used in the parts of the codebase needed to actually enable/disable handling of the program change midi message.

To restore the feature a check is needed in src/Nio/InMgr.cpp around line 137 where M_PGMCHANGE is handled and src/Plugin/ZynAddSubFX/ZynAddSubFX.cpp around line 412 where 0xC0 is handled (i.e. program change).