sws: fallback to mmx2 when yuv2yuvX_sse3() cannot be used.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libswscale/x86/swscale_mmx.c

@@ -180,6 +180,9 @@ static void yuv2yuvX_sse3(const int16_t *filter, int filterSize,
                            const int16_t **src, uint8_t *dest, int dstW,
                            const uint8_t *dither, int offset)
 {
+    if(((int)dest) & 15){
+        return yuv2yuvX_MMX2(filter, filterSize, src, dest, dstW, dither, offset);
+    }
     if (offset) {
         __asm__ volatile("movq       (%0), %%xmm3\n\t"
                          "movdqa    %%xmm3, %%xmm4\n\t"