rockchip: configs: mk808: change CONFIG_TPL_TEXT_BASE

Currently the Rockchip rk3066a u-boot-tpl.bin file needs
to add the characters "RK30", while the other SoCs replace
the first 4 bytes. Bring this in line with the rest by
lowering CONFIG_TPL_TEXT_BASE and update rockchip.rst
instructions.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
2 files changed