inline, defaults to "extern inline" with newer gcc versions

With newer versions of gcc, "inline" defaults to extern, and not static if
not specified. This causes linking problems at the end of the compile. Most
of this occurences are fixed (or #ifdef'ed away) except these two small
ones in timidity/mfi.c

Signed-off-by: Stian Skjelstad <stian.skjelstad@gmail.com>