bcm2835_wdt: support for the BCM2835/2836 watchdog

Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index dfc7fbd..8378601 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -18,3 +18,4 @@
 obj-$(CONFIG_WDT) += wdt-uclass.o
 obj-$(CONFIG_WDT_SANDBOX) += sandbox_wdt.o
 obj-$(CONFIG_WDT_ASPEED) += ast_wdt.o
+obj-$(CONFIG_BCM2835_WDT)       += bcm2835_wdt.o