TRX: Remove extra TCH/HS puncturing value

3GPP TS 05.03 "Channel coding" specifies the puncturing matrix (1,0,1)
for class 1 information bits and tail bits valued u(0) to u(103) for a
maximum puncturing index of 311. The puncturing index 313 exceeds the
maximum index and causes osmo_conv_get_output_length() to output the
improper length of 210 instead of 211.

Signed-off-by: Thomas Tsou <tom@tsou.cc>

src/osmo-bts-trx/gsm0503_conv.c

@@ -139,7 +139,7 @@ static const int conv_tch_hr_puncture[] = {
 	253, 256, 259, 262, 265, 268, 271, 274, 277, 280, 283,
 
 	/* Tail bits */
-	295, 298, 301, 304, 307, 310, 313,
+	295, 298, 301, 304, 307, 310,
 
 	/* End */
 	-1,