watchdog: mx25: use the imx_watchdog driver for mx25

The existing imx_watchdog driver is compatible with mx25 chipsets.
Add a WDOG1_BASE_ADDR define for the base address and enable the driver
in watchdog's Makefile.

To use the driver, a board must define CONFIG_IMX_WATCHDOG and
CONFIG_HW_WATCHDOG.

This fixes an issue when booting an mx25 chip via usb/serial. In this
case, the boot rom will always enable the watchdog. If u-boot is running
in interactive mode and the watchdog is not serviced, the system is
rebooted when the watchdog expires.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index f405f51..08406ca 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -5,7 +5,7 @@
 
 obj-$(CONFIG_AT91SAM9_WATCHDOG) += at91sam9_wdt.o
 obj-$(CONFIG_FTWDT010_WATCHDOG) += ftwdt010_wdt.o
-ifneq (,$(filter $(SOC), mx31 mx35 mx5 mx6 mx7 vf610))
+ifneq (,$(filter $(SOC), mx25 mx31 mx35 mx5 mx6 mx7 vf610))
 obj-y += imx_watchdog.o
 endif
 obj-$(CONFIG_S5P)               += s5p_wdt.o