cmake: dts: Generate edt.json metadata during build

[rruuaanng]

#119

Change the Rust DT generation to read the edtlib parsed tree. This involves extending the
generator in the Rust build to not just generate a Python pickle file of this data, but also
output it in a more portable format, such as json, or yaml, that can be read from the Rust code
that generates the Rust devicetree code.

Generate edt.json during build to enable better devicetree parsing support in Rust.

e.g.

...
        {
            "name": "interrupt-controller@e000e100",
            "compats": [
                "arm,v7m-nvic"
            ],
            "path": "/soc/interrupt-controller@e000e100",
            "labels": [
                "nvic"
            ],
            "aliases": [],
            "status": "okay",
            "dep_ordinal": 4,
            "hash": "MNKByYDCdVxyLwiy4A_bv2jZfVhfDT01mZ2_1uEhUYQ",
            "ranges": [],
            "regs": [
                {
                    "name": null,
                    "addr": "0xe000e100",
                    "size": "0xc00"
                }
            ],
            "props": [
                {
                    "reg": {
                        "spec": {
                            "path": "D:/Code/github/zephyr/zephyr-test/zephyr/dts/bindings\\interrupt-controller\\arm,v7m-nvic.yaml",
                            "type": "array",
                            "enum": null,
                            "const": null,
                            "default": null,
                            "required": true
                        },
                        "val": [
                            3758153984,
                            3072
                        ],
                        "type": "array"
                    }
                },
                {
                    "arm,num-irq-priority-bits": {
                        "spec": {
                            "path": "D:/Code/github/zephyr/zephyr-test/zephyr/dts/bindings\\interrupt-controller\\arm,v7m-nvic.yaml",
                            "type": "int",
                            "enum": null,
                            "const": null,
                            "default": null,
                            "required": true
                        },
                        "val": 4,
                        "type": "int"
                    }
                },
...

[sonarqubecloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[decsny]

I think you need to add testing for this, since it is now more code that is needing to be maintained and people will potentially break it if they dont realize it exists or how its supposed to work when making other changes to this scripting

[mbolivar]

Agreed -- testing would also make it clearer what your intentions are for the data format etc