winecoreaudio.drv: Ensure divide-by-zero SSE exceptions are masked before calling AudioConverterNew.

AudioConverterNew can trigger a divide-by-zero exception. Normally this
is masked by the default SSE mask flags. However, iRacing disables this
mask, leading to a crash when it tries to initialize a recording device.
Signed-off-by: Andrew Eikum <aeikum@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>