UPSTREAM: ARM: dts: rockchip: rename rk3228.dtsi to rk322x.dtsi

UPSTREAM: ARM: dts: rockchip: rename rk3228.dtsi to rk322x.dtsi

We have the brother chipset that RK3228 and RK3229, they share most
of dts configuration, but there are a number of different features.
In order to develop the future when they are easy to distinguish,
we need them to be independent.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
(cherry picked from git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git
v4.8-armsoc/dts32 commit 8372d93df7c265a67676dcd329da9588cc769192)

Change-Id: I0b3c91cddb3ca919b165ba1ec5b2b9466945546d
Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>