Devicetree updates for v4.21: - Initial support for DT bindings using json-schema language. This is the start of converting DT bindings from free-form text to a structured format. - Reworking of initrd address initialization. This moves to using the phys address instead of virt addr in the DT parsing code. This rework was motivated by CONFIG_DEV_BLK_INITRD causing unnecessary rebuilding of lots of files. - Fix stale phandle entries in phandle cache - DT overlay validation improvements. This exposed several memory leak bugs which have been fixed. - Use node name and device_type helper functions in DT code - Last remaining conversions to using %pOFn printk specifier instead of device_node.name directly - Create new common RTC binding doc and move all trivial RTC devices out of trivial-devices.txt. - New bindings for Freescale MAG3110 magnetometer, Cadence Sierra PHY, and Xen shared memory - Update dtc to upstream version v1.4.7-57-gf267e674d145