hier.7/wlan.4: remove reference to wi(4)

The latter has been removed in a21def4d56.

share/man/man4/wlan.4

@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd October 29, 2015
+.Dd January 9, 2021
 .Dt WLAN 4
 .Os
 .Sh NAME
@@ -191,7 +191,6 @@ Stations implementing earlier drafts (e.g., Linux) may be incompatible.
 .Xr upgt 4 ,
 .Xr ural 4 ,
 .Xr urtw 4 ,
-.Xr wi 4 ,
 .Xr wlan_acl 4 ,
 .Xr wlan_ccmp 4 ,
 .Xr wlan_tkip 4 ,

share/man/man7/hier.7

@@ -28,7 +28,7 @@
 .\"	@(#)hier.7	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd November 23, 2020
+.Dd January 9, 2021
 .Dt HIER 7
 .Os
 .Sh NAME
@@ -235,9 +235,6 @@ see
 .Xr ppbus 4
 .It Pa usb/
 USB subsystem
-.It Pa wi/
-.Xr wi 4
-WaveLAN driver
 .El
 .It Pa fs/
 .Bl -tag -width "kerberos5/" -compact