ARM: SoC updates for v5.16

The SoC updates this time are mainly removing obsolete code from the
OMAP2 platform, another step in the eternal cleanup of that platform.

There are two new SoCs getting added: STMicroelectronics stm32mp13 and
Microchip lan966. Both fit into existing platforms and require minimal
changes here.

A couple of MAINTAINER file updates relate to those changes, and
update some file paths.