Log Message:
Update mlterm to 3.8.2.

Change noted in doc/en/ReleaseNote:

ver 3.8.2
* Support page of VT400 or later. (NP, PP, PPA, PPR, PPB, DECCRA and DECLRP)
* Support DECRQDE, DECSCUSR(Ps = 3,4,5,6), DECATC, DECRQM, DECRQMH, DECSCA,
  DECERA, DECSEL and DECSED.
* Support SGR of DECRQSS.
* Support MC and DECMC which output screen contents to \ 
~/.mlterm/[tty]-YYYYMMDDHHMMSS.snp.
* Add "baseline_offset" / --blpos option.
* Revive iiimf input method plugin.
  (--disable-iiimf optoin of configure script disables this feature.)
* Update unicode property table (generated from UnicodeData.txt and
  EastAsianWidth.txt) to version 10.0.0.
* Support brltty with the use of brlapi library. (Experimental)
  (configure with --enable-brlapi option.)
* Enable to build on msys2.
* Support DECDHL and DECDWL on console.
* libvte compatible library supports vte 0.48.0 API.
* Bug fixes:
  Fix unexpected blocking in exiting mlterm.jar.
  Fix a redrawing problem in inserting RTL characters between LTR ones or vice-versa.
  Fix unexpected erasing of DECIC and DECDC.
  Fix a bug which occupies 100% of CPU in switching mlterm-fb to an inactive
  console on linux.
  Fix freeze in copy&paste between windows of libvte compatible library.
  <dev> in OSC 5379;<dev>:a=b works.