Convert CONFIG_USE_ONENAND_BOARD_INIT to Kconfig

This converts the following to Kconfig:
   CONFIG_USE_ONENAND_BOARD_INIT

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index ad36ae6..bb956e3 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1298,6 +1298,10 @@
 	  and erasing blocks. It allso provides a way to show and change
 	  bad blocks, and test the device.
 
+config USE_ONENAND_BOARD_INIT
+	bool "Call onenand_board_init() in the onenand command"
+	depends on CMD_ONENAND
+
 config CMD_OSD
 	bool "osd"
 	help