sigProcLib: Fix number of tail bits in random Normal Bursts and zero Stealing Bits.

This bug only affects generation of normal bursts filled with random bits which
are used in test mode. It doesn't affect operation of osmo-trx during normal
operation. That's why it has stayed unnoticed for so long.

Each Normal Burst has 3 tail bits, not 4.
Also it's better to set stealing bits to 0 for maximum compatibility. We may want to
introduce a selector for each bit whether to set it to 0, to 1 or to a random number.

Change-Id: I0377029556c8b681b3ba3b635bf19572b34546ea

Transceiver52M/sigProcLib.cpp

@@ -927,19 +927,25 @@ signalVector *genRandNormalBurst(int tsc, int sps, int tn)
   signalVector *burst;
 
   /* Tail bits */
-  for (; i < 4; i++)
+  for (; i < 3; i++)
     (*bits)[i] = 0;
 
   /* Random bits */
-  for (; i < 61; i++)
+  for (; i < 60; i++)
     (*bits)[i] = rand() % 2;
 
+  /* Stealing bit */
+  (*bits)[i++] = 0;
+
   /* Training sequence */
   for (int n = 0; i < 87; i++, n++)
     (*bits)[i] = gTrainingSequence[tsc][n];
 
+  /* Stealing bit */
+  (*bits)[i++] = 0;
+
   /* Random bits */
-  for (; i < 144; i++)
+  for (; i < 145; i++)
     (*bits)[i] = rand() % 2;
 
   /* Tail bits */