soc: arm64: add NXP ls1046a support

NXP ls1046a is SoC includes the following functions and features:
1. Four 32/64-bit Arm v8 A72 CPUs
2. Cache coherent interconnect (CCI-400)
3. One 32/64-bit DDR4 SDRAM memory controller with ECC
4. Peripheral interfaces include DPAA network, PCIe, USB, SPI,
   GPIO, UART, SDHC, IFC, LPUART ...

Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com>