smacker: add forgotten *
found by fenrir

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit f98edc73c599badaa0c075fbffb519a150d03d80)
diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c
index f790e08..95a9beb 100644
--- a/libavcodec/smacker.c
+++ b/libavcodec/smacker.c
@@ -660,7 +660,7 @@
     } else { //8-bit data
         for(i = stereo; i >= 0; i--)
             pred[i] = get_bits(&gb, 8);
-        if (stereo + unp_size > data_size)
+        if (stereo + unp_size > *data_size)
             return -1;
         for(i = 0; i < stereo; i++)
             *samples++ = (pred[i] - 0x80) << 8;