* lisp/leim/quail: Use lexical-binding

* lisp/leim/quail: Use lexical-binding

* lisp/leim/quail/hangul.el:
* lisp/leim/quail/indian.el:
* lisp/leim/quail/ipa.el:
* lisp/leim/quail/japanese.el:
* lisp/leim/quail/lao.el:
* lisp/leim/quail/latin-ltx.el:
* lisp/leim/quail/lrt.el:
* lisp/leim/quail/sisheng.el:
* lisp/leim/quail/thai.el:
* lisp/leim/quail/tibetan.el: Use lexical-binding.
* lisp/leim/quail/uni-input.el (ucs-input-method): Remove unused var `str`.