drivers: soc: atmel: add null entry at the end of at91_soc_allowed_list[]

BugLink: https://bugs.launchpad.net/bugs/1916056

commit 6808965 upstream.

of_match_node() calls __of_match_node() which loops though the entries of
matches array. It stops when condition:
(matches->name[0] || matches->type[0] || matches->compatible[0]) is
false. Thus, add a null entry at the end of at91_soc_allowed_list[]
array.

Fixes: caab13b ("drivers: soc: atmel: Avoid calling at91_soc_init on non AT91 SoCs")
Cc: stable@vger.kernel.org #4.12+
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: claudiubeznea

drivers/soc/atmel/soc.c

@@ -268,7 +268,8 @@ static const struct of_device_id at91_soc_allowed_list[] __initconst = {
 	{ .compatible = "atmel,at91rm9200", },
 	{ .compatible = "atmel,at91sam9", },
 	{ .compatible = "atmel,sama5", },
-	{ .compatible = "atmel,samv7", }
+	{ .compatible = "atmel,samv7", },
+	{ }
 };
 
 static int __init atmel_soc_device_init(void)