net: ieee802154: adf7242: Fix bug if defined DEBUG

[ Upstream commit 388b3b2b03701f3b3c10975c272892d7f78080df ]

This fixes undefined reference to struct adf7242_local *lp in
case DEBUG is defined.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>