dca: add emms_c after usage of AV_COPY128

Similar to AV_ZERO128, AV_COPY128 can use MMX instructions in x86

libavcodec/dca_core.c

@@ -992,6 +992,8 @@ static int parse_frame_data(DCACoreDecoder *s, enum HeaderType header, int xch_b
         }
     }
 
+    emms_c();
+
     return 0;
 }
 
@@ -1668,6 +1670,8 @@ static int parse_x96_frame_data(DCACoreDecoder *s, int exss, int xch_base)
         }
     }
 
+    emms_c();
+
     return 0;
 }