improved help: incorrect entries are ignored without further warning

Author: =

hcxdumptool.c

@@ -5500,6 +5500,7 @@ fprintf(stdout, "%s %s  (C) %s ZeroBeat\n"
 	"-c <digit>       : set channel (1a,2a,36b,...)\n"
 	"                    default: 1a,6a,11a\n"
 	"                    important notice: channel numbers are not unique\n"
+	"                    incorrect entries are ignored without further warning\n"
 	"                    it is mandatory to add band information to the channel number (e.g. 12a)\n"
 	"                     band a: NL80211_BAND_2GHZ\n"
 	"                     band b: NL80211_BAND_5GHZ\n"
@@ -5510,6 +5511,7 @@ fprintf(stdout, "%s %s  (C) %s ZeroBeat\n"
 	#endif
 	"                    to disable frequency management, set this option to a single frequency/channel\n"
 	"-f <digit>       : set frequency (2412,2417,5180,...)\n"
+	"                    incorrect entries are ignored without further warning\n"
 	"-F               : use all available frequencies from INTERFACE\n"
 	"-t <second>      : minimum stay time (will increase on new stations and/or authentications)\n"
 	"                    default %d seconds\n"