YADIF : Code the instruction width into 'cmp'.

Without this, clang will complain about the asm block.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/video_filter/yadif.h

@@ -154,7 +154,7 @@ static void yadif_filter_line_mmx2(struct vf_priv_s *p, uint8_t *dst, uint8_t *p
 \
             /* if(p->mode<2) ... */\
             "movq    %[tmp3], %%mm6 \n\t" /* diff */\
-            "cmp       $2, %[mode] \n\t"\
+            "cmpl       $2, %[mode] \n\t"\
             "jge       1f \n\t"\
             LOAD4("(%["prev2"],%[mrefs],2)", %%mm2) /* prev2[x-2*refs] */\
             LOAD4("(%["next2"],%[mrefs],2)", %%mm4) /* next2[x-2*refs] */\