net: appletalk: Kconfig: Fix docs location

The location of ltpc.rst changed. Update it at Kconfig.

Fixes: 4daedf7a ("docs: networking: move AppleTalk / LocalTalk drivers to the hw driver section")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/net/appletalk/Kconfig

@@ -48,7 +48,7 @@ config LTPC
 	  If you are in doubt, this card is the one with the 65C02 chip on it.
 	  You also need version 1.3.3 or later of the netatalk package.
 	  This driver is experimental, which means that it may not work.
-	  See the file <file:Documentation/networking/ltpc.rst>.
+	  See the file <file:Documentation/networking/device_drivers/appletalk/ltpc.rst>.
 
 config COPS
 	tristate "COPS LocalTalk PC support"