Log Message:
Update mlterm to 3.4.3.

Changes noted in doc/en/ReleaseNote:

ver 3.4.3
* Support true type fonts with the use of freetype library (./configure \ 
--enable-anti-alias)
  on framebuffer and Android.
* Support ISCII proportional fonts with the use of freetype library on \ 
framebuffer and
  Android.
* Drop -C/--ind/use_ind and -D/--bi/use_bidi options. Add -C/--ctl/use_ctl \ 
option which
  enables or disables both rendering bi-directional text and indic scripts.
* --deffont/default_font option and vte_terminal_set_font* functions of libvte \ 
compatible
 library overwrite the default font of "ISO10646_UCS4_1" not only \ 
"DEFAULT".
* Simplify font configuration of OSC 5380 and 5381.
  (e.g.) 'mlcc font USASCII' returns \ 
"#ISO8859_1,12=-mplus-*-medium-r-*--12-*-iso8859-1")
* Bug fixes:
  Fix the position of a candidate window of fcitx. (Thanks to @msmhrt)
  Fix frozen screen in preediting text by soft keyboard on Android. (Thanks to \ 
@mikoto2000)