Add .recent syntax element to cdlms struct

(cherry picked from commit a7820f3c5a)

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

libavcodec/wmalosslessdec.c

@@ -253,6 +253,7 @@ typedef struct WmallDecodeCtx {
         int16_t coefs[256];
     int lms_prevvalues[512];    // FIXME: see above
     int16_t lms_updates[512];   // and here too
+    int recent;
     } cdlms[2][9];              /* XXX: Here, 2 is the max. no. of channels allowed,
                                         9 is the maximum no. of filters per channel.
                                         Question is, why 2 if WMALL_MAX_CHANNELS == 8 */