Move docparse/README.md to metadata/ directory

docparse/ directory will be removed in the next commit. README.md should
be converted to sphinx documentation in doc/, but keep it until done.

Link: https://lore.kernel.org/ltp/20250207105551.1736356-6-pvorel@suse.cz/
Acked-by: Andrea Cervesato <andrea.cervesato@suse.com>
Signed-off-by: Petr Vorel <pvorel@suse.cz>

Author: pevik