[top/doc] Autogenerated tables for top-specific IP

We have several top-level specific IPs for which the configuration is not evident from the technical IP specification alone.
Examples are the plic, alert handler, pinmux, pwrmgr, rstmgr, clkmgr.

For some of these, we do already generate top-level specific documentation, such as for example the pinout and pinmux configuration tables [here](https://opentitan.org/book/hw/ip/pinmux/doc/programmers_guide.html#top-earlgrey) for the block and [here](https://opentitan.org/book/hw/top_earlgrey/doc/design/index.html#pinout) for the top-level (both with different scripts, which is another thing that may be unified at some point).

It would probably be good to enhance documentation for the IPs mentioned above to follow this example so that SW developers can find that information more readily.