new: devel/libmarisa: tire library wanted by some IME pkgs

Hi,

The attached port is a C++ library for MARISA, which is a static and
space-efficient trie data structure. This library is used by IME related
packages such as libskk and librime, which I would like to import in
future.

I tested it on the following platforms using the included
marisa-benchmark command, and with all titles in English wikipedia as
input. It works fine.

Tested on:
amd64
aarch64 (rpi4)
mips64el (loongson) (with reduced input)

... all running the latest snapshot.

The tarball is also available on the web:
https://github.com/ZhanYF/static/raw/main/libmarisa.tar

comments? ok to import?