arm: rockchip: Add RK3588 arch core support

The Rockchip RK3588 is a ARM-based SoC with quad-core Cortex-A76
and quad-core Cortex-A55 including NEON and GPU, 6TOPS NPU,
Mali-G610 MP4, HDMI Out, HDMI In, DP, eDP, MIPI DSI, MIPI CSI2,
LPDDR4/4X/5, eMMC5.1, SD3.0/MMC4.5, USB OTG 3.0, Type-C, USB 2.0,
PCIe 3.0, SATA 3, Ethernet, SDIO3.0 I2C, UART, SPI, GPIO and PWM.

Add arch core support for it.

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