ac3dsp: Change punpckhqdq to movhlps in ac3_max_msb_abs_int16().

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
(cherry picked from commit 1f004fc512)

libavcodec/x86/ac3dsp.asm

@@ -110,8 +110,7 @@ cglobal ac3_max_msb_abs_int16_%1, 2,2,5, src, len
     por         m2, m3
 %endif
 %ifidn mmsize, 16
-    mova        m0, m2
-    punpckhqdq  m0, m0
+    movhlps     m0, m2
     por         m2, m0
 %endif
     PSHUFLW     m0, m2, 0xe