dts: nordic: Add properties indicating certain peripheral features

Add boolean properties to the binding for the nRF RADIO peripheral
to indicate whether the following features are supported:
- IEEE 802.15.4 mode
- 2 Mbps BLE mode
- coded BLE PHY
- high TX power settings
Set these properties appropriately in devicetree radio nodes for all
nRF SoCs.

Add also such properties and set them in appropriate nodes for nRF
flash controllers to indicate whether they support partial erase.

Signed-off-by: Andrzej Głąbek <andrzej.glabek@nordicsemi.no>