[Mingw-cross-env-list] Five packages crash 'make update'.

[Niels Kristian Bech Jensen]

These five packages crash 'make update'. I had to add ignore code (like in freetds.mk) to their .mk files to get the update completed:
 
json-c
libharu
sdl_gfx
twolame
wavpack
 
The first three packages just would not update. The last two complained about un-terminated sed strings.
 
Best regards,
Niels Kristian Bech Jensen