[reggen] skipto error fix

Previous fix #654 wasn't correct.

Problem:

    `skipto` field value should be string as shown in example, not
    integer. But `rv_plic.hjson.tpl` set it to integer type. It results
    in to wrap the value with `hex()` to make it string type.

    This make the rv_plic reports correct error but it let build_docs.py
    failed.

```
Traceback (most recent call last):
  File "./util/build_docs.py", line 165, in <module>
    main()
  File "./util/build_docs.py", line 151, in main
    process_all_files()
  File "./util/build_docs.py", line 127, in process_all_files
...
  File "/mistletoe/base_renderer.py", line 95, in render
    return self.render_map[token.__class__.__name__](token)
  File "util/docgen/lowrisc_renderer.py", line 301, in render_lowrisc_escape
    if validate.validate(obj) == 0:
  File "util/reggen/validate.py", line 1363, in validate
    " which is not a multiple of the register size " +
TypeError: 'str' object cannot be interpreted as an integer
```

Resolution:

    Rolled-back the `validate.py` error report code. And changed
    `rv_plic.hjson.tpl` to make `skipto` to string type.

Issue reported by @asb
4 files changed
tree: e17b1eba210860ae005a7b454b46702bbdfbf49a
  1. .github/
  2. ci/
  3. doc/
  4. hw/
  5. site/
  6. sw/
  7. test/
  8. util/
  9. .clang-format
  10. .gitignore
  11. .style.yapf
  12. azure-pipelines.yml
  13. CONTRIBUTING.md
  14. index.md
  15. LICENSE
  16. meson.build
  17. meson_init.sh
  18. meson_options.txt
  19. python-requirements.txt
  20. README.md
  21. sitemap.md
  22. toolchain.txt
README.md

OpenTitan

This repository contains hardware, software and utilities written as part of the OpenTitan project. It is structured as monolithic repository, or “monorepo”, where all components live in one repository.

Documentation

The project contains comprehensive documentation of all IPs and tools. You can either access it online or build it locally by following the steps below.

  1. Ensure that you have the required Python modules installed (to be executed in the repository root):
$ sudo apt install python3 python3-pip
$ pip3 install --user -r python-requirements.txt
  1. Execute the build script:
$ ./util/build_docs.py --preview

This compiles the documentation into ./opentitan-docs and starts a local server, which allows you to access the documentation at http://127.0.0.1:5500.

How to contribute

Have a look at CONTRIBUTING.md for guidelines how to contribute code to this repository.

Licensing

Unless otherwise noted, everything in this repository is covered by the Apache License, Version 2.0 (see LICENSE for full text).