tfm: nordic_nrf: Add generic SoC support for nordic SoCs

Add generic SoC support for the supported nordic SoCs:
- nrf5340
- nrf9160
- nrf9120

Add generic SoC support by taking board specific configurations from
zephyr devicetree and kconfig.

Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>
22 files changed