arm: rockchip: Add RV1126 arch core support

Rockchip RV1126 is a high-performance vision processor SoC
for IPC/CVR, especially for AI related application.

Add arch core support for it.

Signed-off-by: Jagan Teki <jagan@edgeble.ai>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Change-Id: I22fde40ec375e3c6aba39808abf252edc45d4b04