icmp: remove unused BANDLIM_UNLIMITED

Reviewed by:		Nick Banks
MFC after:		1 week
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D51849

sys/netinet/icmp_var.h

@@ -100,7 +100,6 @@ void	kmod_icmpstat_inc(int statnum);
 SYSCTL_DECL(_net_inet_icmp);
 
 extern int badport_bandlim(int);
-#define BANDLIM_UNLIMITED -1
 #define BANDLIM_ICMP_UNREACH 0
 #define BANDLIM_ICMP_ECHO 1
 #define BANDLIM_ICMP_TSTAMP 2

sys/netinet/ip_icmp.c

@@ -1181,7 +1181,7 @@ badport_bandlim(int which)
 {
 	int64_t pps;
 
-	if (V_icmplim == 0 || which == BANDLIM_UNLIMITED)
+	if (V_icmplim == 0)
 		return (0);
 
 	KASSERT(which >= 0 && which < BANDLIM_MAX,