wifi manuals: Mlink + document description consistency

Interfaces all have an mlink to if_$foo. Add these for the missing ones
and remove an incorrect one from rtwn_pci. Wireless network drivers are
all accessible via `apropos -s4 "wireless network driver", except two
which are "wireless network device". I actually prefer the latter, but
make them all consistent upon the more common parlance. Tag SPDX on one
of the files I touched, while here.

MFC after:		3 days
Reviewed by:		bz, carlavilla, mhorne
Approved by:		carlavilla, mhorne (mentors)
Differential Revision:	https://reviews.freebsd.org/D49063

(cherry picked from commit 4262dbc57982383eb61a8b7806de6dd4b7802da8)

share/man/man4/Makefile

@@ -742,7 +742,9 @@ MLINKS+=ptnet.4 if_ptnet.4
 MLINKS+=ral.4 if_ral.4
 MLINKS+=re.4 if_re.4
 MLINKS+=rl.4 if_rl.4
-MLINKS+=rtwn_pci.4 if_rtwn_pci.4
+MLINKS+=rtw88.4 if_rtw89.4
+MLINKS+=rtw89.4 if_rtw89.4
+MLINKS+=rtwn.4 if_rtwn.4
 MLINKS+=rue.4 if_rue.4
 MLINKS+=scsi.4 CAM.4 \
 	scsi.4 cam.4 \

share/man/man4/uath.4

@@ -1,4 +1,6 @@
 .\"
+.\" SPDX-License-Identifier: ISC
+.\"
 .\" Copyright (c) 2006
 .\"     Damien Bergamini <damien.bergamini@free.fr>
 .\"
@@ -19,7 +21,7 @@
 .Os
 .Sh NAME
 .Nm uath
-.Nd Atheros USB IEEE 802.11a/b/g wireless network device
+.Nd Atheros USB IEEE 802.11a/b/g wireless network driver
 .Sh SYNOPSIS
 To compile this driver into the kernel,
 place the following lines in your

share/man/man4/upgt.4

@@ -54,7 +54,7 @@
 .Sh NAME
 .Nm upgt
 .Nd Conexant/Intersil PrismGT SoftMAC USB IEEE 802.11b/g wireless network
-device
+driver
 .Sh SYNOPSIS
 To compile this driver into the kernel,
 place the following lines in your