mailbox: change mailbox-mpfs compatible string

The Polarfire SoC is currently using two different compatible string
prefixes. Fix this by changing "polarfire-soc-*" strings to "mpfs-*" in
its system controller in order to match the compatible string used in
the soc binding and device tree.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/mailbox-mpfs.c

@@ -232,7 +232,7 @@ static int mpfs_mbox_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id mpfs_mbox_of_match[] = {
-	{.compatible = "microchip,polarfire-soc-mailbox", },
+	{.compatible = "microchip,mpfs-mailbox", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, mpfs_mbox_of_match);