spi/rockchip: add the rk3036/rk3228/rk3368 to match for driver

In gerenal, the "rockchip,rockchip-spi" string will match the dts
that's great in spi driver. After all the most of rockchip SoCs ar
same spi controller.

Then, we should keep the old style to match the dts various.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>