DirectDraw: do not save a string that is deallocated immediately after.

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>
DirectDraw: DirectDrawEnumerateExW does not work, use DirectDrawEnumerateExA instead.

Fix #10189, #10307.

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>