arm64: dts: add QorIQ LS1046A SoC support

LS1046A is an SoC with 4 ARMv8 A72 cores and most other IP blocks
are similar to LS1043A which also complies to Freescale Chassis 2.1
spec.

Created LS1046A SoC DTSI file to be included by board level DTS
files.

Signed-off-by: Horia Geant? <[email protected]>
Signed-off-by: Mihai Bantea <[email protected]>
Signed-off-by: Chenhui Zhao <[email protected]>
Signed-off-by: Gong Qianyu <[email protected]>
Signed-off-by: Minghuan Lian <[email protected]>
Signed-off-by: Hou Zhiqiang <[email protected]>
Signed-off-by: Mingkai Hu <[email protected]>
Signed-off-by: Shaohui Xie <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>