[$] A new version of modversions

The genksyms tool has long been buried deeply within the kernel's
build system; it is one of the two C-code parsers shipped with the kernel
(the other being the
horrifying kernel-doc script). It is a key part of how the
kernel's module-loading infrastructure works. While genksyms has
quietly done its job for decades, that period may soon be coming to an end.
It would seem that genksyms is not up to the task of handling Rust
code, so Sami Tolvanen is proposing
a new tool to handle this task going forward.