qdm2: disable superblocktype_2_3==0 code

The code is untested and contained bugs, we need a sample if any files
use this branch.

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

libavcodec/qdm2.c

@@ -649,7 +649,8 @@ static void fill_coding_method_array (sb_int8_array tone_level_idx, sb_int8_arra
 
     if (!superblocktype_2_3) {
         /* This case is untested, no samples available */
-        SAMPLES_NEEDED
+        av_log_ask_for_sample(NULL, "!superblocktype_2_3");
+        return;
         for (ch = 0; ch < nb_channels; ch++)
             for (sb = 0; sb < 30; sb++) {
                 for (j = 1; j < 63; j++) {  // The loop only iterates to 63 so the code doesn't overflow the buffer