moused(8): Add command line option to restrict interface type

to evdev or sysmouse. It is required to avoid receiving of double events
on hybrid devices supporting both interfaces like ums (4).

MFC after:	1 day
Reviewed by:	glebius (via private chat)
Differential Revision:	https://reviews.freebsd.org/D52647

libexec/rc/rc.conf

@@ -589,7 +589,7 @@ saver="NO"		# screen saver: Uses /boot/kernel/${saver}_saver.ko
 moused_nondefault_enable="NO" # Treat non-default mice as enabled unless
 			       # specifically overridden in rc.conf(5).
 moused_enable="NO"	# Run the mouse daemon.
-moused_type="auto"	# See man page for rc.conf(5) for available settings.
+moused_type="evdev"	# See man page for rc.conf(5) for available settings.
 moused_port="auto"	# Set to your mouse port.
 moused_flags=""		# Any additional flags to moused.
 mousechar_start="NO"	# if 0xd0-0xd3 default range is occupied in your

libexec/rc/rc.d/moused

@@ -16,6 +16,7 @@ start_cmd="moused_start"
 pidprefix="/var/run/moused"
 pidfile="${pidprefix}.pid"
 pidarg=
+typearg=
 load_rc_config $name
 
 # doesn't make sense to run in a svcj: nojail keyword
@@ -49,15 +50,17 @@ moused_start()
 		eval myflags=\${moused_${ms}_flags-$moused_flags}
 		eval myport=\${moused_${ms}_port-/dev/$ms}
 		eval mytype=\${moused_${ms}_type-$moused_type}
+		if [ -n "$mytype" ] && check_kern_features evdev_support; then
+			typearg="-t ${mytype}"
+		fi
 	else
 		ms="default"
 		myflags="$moused_flags"
 		myport="$moused_port"
-		mytype="$moused_type"
 	fi
 
 	startmsg -n "Starting ${ms} moused"
-	/usr/sbin/moused ${myflags} -p ${myport} -t ${mytype} ${pidarg}
+	/usr/sbin/moused ${myflags} -p ${myport} ${typearg} ${pidarg}
 	startmsg '.'
 
 	mousechar_arg=