unicode.h: set console mode before using wprintf
unicode.h: set console mode before using wprintf

This fixes incorrect character display in the file name
in e.g., stats output from cwebp.exe in visual studio builds.

In mingw further changes will be needed as using %s in wfprintf() for
wchar_t pointers is a Microsoft extension that doesn't seem to be
supported with gcc -fms-extensions. %ls works, but will require updating
format strings and wrapping concatenations with TO_W_CHAR() as visual
studio will reject merging string constants of different width.

https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/setmode

Change-Id: I57d24c3815f7b5aa3971ac315c65c4458258d706

webmproject/libwebp,webmproject/libwebp,webmproject/libwebp,webmproject/libwebp,webmproject/libwebp