watchdog: Add booke watchdog driver

Add a driver for the PowerPC Book E watchdog driver that is present on a
number of Freescale/NXP SoCs.

Signed-off-by: Chris Packham <judge.packham@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index aa76a8f..f0ff261 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -124,6 +124,13 @@
 	  The watchdog timer is stopped when initialized.
 	  It performs full SoC reset.
 
+config WDT_BOOKE
+	bool "PowerPC Book-E watchdog driver"
+	depends on WDT && MPC85xx
+	help
+	  Watchdog driver for PowerPC Book-E chips, such as the Freescale
+	  MPC85xx SOCs and the IBM PowerPC 440.
+
 config WDT_CDNS
 	bool "Cadence watchdog timer support"
 	depends on WDT