common: bootdelay: move CONFIG_BOOTDELAY into a Kconfig option

move CONFIG_BOOTDELAY into a Kconfig option. Used for this
purpose the moveconfig.py tool in tools.

Signed-off-by: Heiko Schocher <hs@denx.de>

Reviewed-by: Tom Rini <trini@konsulko.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
diff --git a/configs/silk_defconfig b/configs/silk_defconfig
index 0beef09..f5d7afd 100644
--- a/configs/silk_defconfig
+++ b/configs/silk_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_RMOBILE=y
 CONFIG_TARGET_SILK=y
+CONFIG_BOOTDELAY=3
 # CONFIG_CMD_BDI is not set
 # CONFIG_CMD_CONSOLE is not set
 # CONFIG_CMD_BOOTD is not set