Convert CONFIG_USE_BOOTCOMMAND et al to Kconfig

This converts the following to Kconfig:
   CONFIG_USE_BOOTCOMMAND
   CONFIG_BOOTCOMMAND
   CONFIG_RAMBOOTCOMMAND
   CONFIG_NFSBOOTCOMMAND

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/omap3_logic_defconfig b/configs/omap3_logic_defconfig
index 0142a7a..8616a65 100644
--- a/configs/omap3_logic_defconfig
+++ b/configs/omap3_logic_defconfig
@@ -15,7 +15,7 @@
 CONFIG_LTO=y
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_ANDROID_BOOT_IMAGE=y
-# CONFIG_USE_BOOTCOMMAND is not set
+CONFIG_BOOTCOMMAND="run autoboot"
 CONFIG_USE_PREBOOT=y
 CONFIG_PREBOOT="setenv preboot;saveenv;"
 CONFIG_SYS_CONSOLE_INFO_QUIET=y