ng_iface(4): Remove unsupported protocols.

Update the ng_iface documentation and hooks to reflect the fact that the
node currently only supports IPv4 and v6 packets.

Reviewed by:	Lutz Donnerhacke
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D25862

share/man/man4/ng_iface.4

@@ -35,7 +35,7 @@
 .\" $FreeBSD$
 .\" $Whistle: ng_iface.8,v 1.5 1999/01/25 23:46:26 archie Exp $
 .\"
-.Dd February 6, 2019
+.Dd July 31, 2020
 .Dt NG_IFACE 4
 .Os
 .Sh NAME
@@ -70,7 +70,7 @@ Packets transmitted via the interface flow out the corresponding
 protocol-specific hook.
 Similarly, packets received on a hook appear on the interface as
 packets received into the corresponding protocol stack.
-The currently supported protocols are IP, IPv6, ATM, NATM, and NS.
+The currently supported protocols are IP and IPv6.
 .Pp
 An
 .Nm iface
@@ -87,12 +87,6 @@ This node type supports the following hooks:
 Transmission and reception of IP packets.
 .It Va inet6
 Transmission and reception of IPv6 packets.
-.It Va atm
-Transmission and reception of ATM packets.
-.It Va natm
-Transmission and reception of NATM packets.
-.It Va ns
-Transmission and reception of NS packets.
 .El
 .Sh CONTROL MESSAGES
 This node type supports the generic control messages, plus the following:

sys/netgraph/ng_iface.c

@@ -111,8 +111,6 @@ typedef const struct iffam *iffam_p;
 const static struct iffam gFamilies[] = {
 	{ AF_INET,	NG_IFACE_HOOK_INET	},
 	{ AF_INET6,	NG_IFACE_HOOK_INET6	},
-	{ AF_ATM,	NG_IFACE_HOOK_ATM	},
-	{ AF_NATM,	NG_IFACE_HOOK_NATM	},
 };
 #define	NUM_FAMILIES		nitems(gFamilies)
 

sys/netgraph/ng_iface.h

@@ -54,8 +54,6 @@
 /* My hook names */
 #define NG_IFACE_HOOK_INET		"inet"
 #define NG_IFACE_HOOK_INET6		"inet6"
-#define NG_IFACE_HOOK_ATM		"atm"
-#define NG_IFACE_HOOK_NATM		"natm"
 
 /* MTU bounds */
 #define NG_IFACE_MTU_MIN		72