make this actually be GCC 12.3.0's libsanitizer.

the libsanitizer we used with GCC 9 and GCC 10 was significantly
ahead of the GCC 9 and GCC 10 provided versions.

initial merge of GCC 12.3.0.

this doesn't include any of the changes to the .c -> .cc files renamed,
and reverts our local changes to the vax port and libsanitizer subdir.
vax GCC was rewritten and our local fixes no longer are relevant, and
the new libsanitizer is more updated than our old one, and merging via
gcc10->gcc12 is not really possible.

unfortunately, our local changes to libsanitizer that aren't related
to the general update of those sources (ie, the netbsd code) will need
to be re-checked and perhaps re-ported.

revert sanitizer back to the version we were using with GCC 9, since
that one was already newer than the GCC 10 version.

branches: 1.1.1;
Initial revision