[opus] [Feature Request] Allow opus-tools from git to be cross-compiled with mingw.

[bat guano]

> 
> > Please fix it so that opus-tools from git can be cross-compiled with mingw.
> 
This commit has fixed it ---> http://git.xiph.org/?p=opus-tools.git;a=commit;h=d2ca877ff7dc38401b3c477208d322f25c18eb8d

@xubuntu:~/Desktop$ wine ./opusenc -V
opusenc opus-tools 0.1.5git (using libopus 1.0.1)

Thanks
;-)