[ot] scripts/opentitan: autoreg.py: add support for multiple file format generation

Add baremetal test template file generation to exiting QEMU device template file generation
Add 'window' register initial support

When interrupt definition use shared fields and contain a mix set of
access type, INTR_ register have a write mask that do not cover the RO
bits; however the INTR_TEST write mask should map all interrupt bits.

Signed-off-by: Emmanuel Blot <[email protected]>

Author: rivos-eblot

docs/opentitan/tools.md

@@ -36,7 +36,7 @@ of options and the available features.
 ## Development
 
 * [`autoregs.py`] is a Python script that generates register definitions and function templates to
-  create a QEMU system bus device emulation.
+  create a skeleton file QEMU system bus device emulation.
 * [`checkregs.py`](checkregs.md) is an internal tool design to check the discrepancies between
    OpenTitan generated register definition files and their QEMU counterparts. It is only useful to
    develop the machine itself.