[flac-dev] ensure that stack is aligned for SSE functions if using mingw32

[lvqcl]

Tristan Matthews wrote:

> Unable to test on win32 at the moment, please give this a try. Feedback welcome.


I wonder why misaligned stack is a problem only for the FLAC library.
There are many other libraries inside VLC...

BTW: FLAC 1.3.1 uses -msse2 option by default. Do you remove it?
Otherwise libFLAC may crash anywhere else (if its stack is not aligned).