dt-bindings: firmware: imx: Move system control into dt-binding headfile

i.MX8 SoCs DTS file needs system control macro definitions, so move them
into dt-binding headfile, then include/linux/firmware/imx/types.h can be
removed and those drivers using it should be changed accordingly.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>