RDL naming convention enforcement and updates

[nathanaelhuffman]

Working with @mkeeter we're adding some improvements to the RDL generation and I've made some naming convention enforcement to help facilitate programatic consumption of the generated artifacts.

New Features:

• added "orig_type_name" to top level addrmap json so that the instance name can be linked with the actual hardware generated .json. Remember, we may have multiple copies of the same "hw" with different instance names.
• added "addr_span_bytes" to the top level addrmap json to give a hint to sw tool generation how many registers we have specified. Note that there's a missing feature from SystemRDL spec that would allow reserving undefined register space, so we're stuck telling sizes that are based only on what we've defined. From a hw implementation perspective, it's certainly safe to assume the peripheral owns up to the next power of 2 here, and possibly with a floor of 256byte addresses.

New Enforcement:

• To provide some naming consistency, we're now enforcing that buck2 rdl targets end with "_rdl" so that it's easier to reason about, and then enforce that output file names (which are user-specified) conform to the expected patterns for software consumption. There are more improvements to be made here RDL addr map name enforcement when doing buck builds #301 but this is a functional start.

The new enforcement regime required doing some updates to various things as seen in this PR as well.

[Aaron-Hartwig]

I am a fan of this!