Deprecate secondary register area for rk3188 pulls. Instead use big enough
initial mapping of grf registers to catch all.

The now deprecated register is still supported though.
Signed-off-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NMax Schwarz <max.schwarz@online.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>