* lisp/emacs-lisp/bindat.el (bindat--pack-strz): For fixed-length strz
fields, explicitly write a null terminator after the packed string if
there is room (bug#56048).
* doc/lispref/processes.texi (Bindat Types): Update documentation.
* test/lisp/emacs-lisp/bindat-tests.el (bindat-test--str-strz-prealloc):
Update tests.