parse_tcpdump_log.pl: Improve help

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/contrib/parse_tcpdump_log.pl b/contrib/parse_tcpdump_log.pl
index 5c43baa..a29a4a4 100755 (executable)
--- a/contrib/parse_tcpdump_log.pl
+++ b/contrib/parse_tcpdump_log.pl
@@ -593,7 +593,13 @@ Prints the manual page and exits.
 
 =item B<--debug> [log level]
 
-Changes the debug log level.
+Changes the debug log level. The available levels are:
+
+       1 - frame request and frame response
+
+       2 - parsed frames
+
+       4 - raw data
 
 =item B<--pcap>