Kconfig: make NOR_BOOT a common option

Not only am335x supports booting from NOR, i.MX6 SoCs also
supports booting from NOR. Make NOR_BOOT a common
option to let different SoCs share it.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Heiko Schocher <hs@denx.de>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Christophe Ricard <christophe-h.ricard@st.com>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Francois Retief <fgretief@spaceteq.co.za>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

board/ti/am335x/Kconfig

@@ -29,15 +29,6 @@ config NOR
 	  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.
-
 source "board/ti/common/Kconfig"
 
 endif

common/Kconfig

@@ -97,6 +97,19 @@ config BOOTSTAGE_STASH_SIZE
 
 endmenu
 
+menu "Boot media"
+
+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.
+
+endmenu
+
 config BOOTDELAY
 	int "delay in seconds before automatically booting"
 	default 2