am335x_evm: Convert NOR_BOOT to Kconfig

Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/board/ti/am335x/Kconfig b/board/ti/am335x/Kconfig
index 1878e36..1ddbb2c 100644
--- a/board/ti/am335x/Kconfig
+++ b/board/ti/am335x/Kconfig
@@ -29,4 +29,12 @@
 	  In practice this is seen as a NOR flash module connected to the
 	  "memory cape" for the BeagleBone family.
 
+config NOR_BOOT
+	bool "Support for booting from NOR flash"
+	depends on NOR
+	help
+	  Enabling this will make a U-Boot binary that is capable of being
+	  booted via NOR.  In this case we will enable certain pinmux early
+	  as the ROM only partially sets up pinmux.  We also default to using
+	  NOR for environment.
 endif