scripts: ci: introduce soc name check in check_compliance

soc.yml files define SoC names which are used in board.yml.
All SoC names and directories are exported to the build system and
can be referenced using the SoC name as identifier.

Kconfig defines a CONFIG_SOC setting with the same name which can be
used in build system and is selected by the board.

Thus the CONFIG_SOC value can be used to lookup the details of the SoC.

This commit introduces a new compliance check which ensures the SoC name
and the CONFIG_SOC name value are in sync.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>