tshark: fix double memory free when analyzing several RTP streams

Bug: 12430
Change-Id: I4f77aee4102edb9d5d8d450de962ca1f4b33bb71
Reviewed-on: https://code.wireshark.org/review/15434


Petri-Dish: Pascal Quantin <pascal.quantin@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Pascal Quantin <pascal.quantin@gmail.com>

ui/cli/tap-rtp.c

@@ -124,7 +124,6 @@ rtp_streams_stat_draw(void *arg _U_)
 
         list = g_list_next(list);
 
-        g_free(payload_type);
         wmem_free(NULL, src_addr);
         wmem_free(NULL, dst_addr);
         wmem_free(NULL, payload_type);