[U-Boot] [U-Boot, 1/2] rockchip: fix turning off boot-mode via Kconfig

[Philipp Tomsich]

> The ROCKCHIP_BOOT_MODE_REG option defaults to a hex value, so 0 will
> show as 0x0.  Consequently, the "is set to something other than 0" test
> in a Makefile needs to be an ifneq($(CONFIG_ROCKCHIP_BOOT_MODE_REG), 0x0).
> 
> This commit fixes mach-rockchip/Makefile and also resulting link
> issues (if boot_mode.o is not included) by defining a stub function
> (in case the functionality is not built in) for setup_boot_mode in
> boot_mode.h.
> 
> Fixes: e306779 (rockchip: make boot_mode related codes reused across all platforms)
> Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> ---
> 
>  arch/arm/include/asm/arch-rockchip/boot_mode.h | 6 ++++++
>  arch/arm/mach-rockchip/Makefile                | 2 +-
>  2 files changed, 7 insertions(+), 1 deletion(-)
> 

Applied to u-boot-rockchip, thanks!