inet.4 tcp.4 udp.4: update date, fix typo

Update .Dd for man pages pushed yesterday; fix typo in inet.4.

share/man/man4/inet.4

@@ -28,7 +28,7 @@
 .\"     From: @(#)inet.4	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd November 12, 2021
+.Dd July 14, 2022
 .Dt INET 4
 .Os
 .Sh NAME
@@ -166,7 +166,7 @@ there are a number of general variables implemented in the
 branch of the
 .Xr sysctl 3
 MIB.
-The following general variabls are defined:
+The following general variables are defined:
 .Bl -tag -width ".Va accept_sourceroute"
 .It Va forwarding
 Boolean: enable/disable forwarding of IP packets.

share/man/man4/tcp.4

@@ -34,7 +34,7 @@
 .\"     From: @(#)tcp.4	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd January 8, 2022
+.Dd July 14, 2022
 .Dt TCP 4
 .Os
 .Sh NAME

share/man/man4/udp.4

@@ -28,7 +28,7 @@
 .\"     @(#)udp.4	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd February 6, 2017
+.Dd July 14, 2022
 .Dt UDP 4
 .Os
 .Sh NAME