Maintain the XML syntax versioning

[ganeshgore]

Is your feature request related to a problem? Please describe. Due to the active and rapid development of this project, the XML syntax is constantly evolving.

• Need to define extra default argument
• Rewrite the XML structure in a different form
• Renaming some conflicting parameter

In some cases, this creates a back-compatibility issue. Currently, this is maintained by updating all existing XML files. Also, once the architecture in finalized or the chip is tapeout HW designers are reluctant to change anything in the source, but SW is continuously evolving.

Describe the solution you'd like We can add a syntax version system,

• Start of the XML file can specified syntax version
• The version is upgraded whenever the new syntax has been introduced, which can not be handled by default values,

Possible implementation flow A simple python-based preprocessing step can upgrade any existing XML file to the current XML file before copying it to the run directory and compiling it.

Additional context This is important to provide long term support