harfbuzz: upgrade 4.3.0 -> 4.4.0

harfbuzz: upgrade 4.3.0 -> 4.4.0

Changelog:
==========
- Caching of variable fonts shaping, in particular when using HarfBuzz’s own
  font loading functions (ot). Bringing performance of variable shaping in par
  with non-variable fonts shaping.
- Caching of format 2 “Contextual Substitution” and “Chained Contexts
  Substitution” lookups. Resulting in up to 20% speedup of lookup-heavy fonts
  like Gulzar or Noto Nastaliq Urdu.
- Improved ANSI output from hb-view.
- Support for shaping legacy, pre-OpenType, Windows 3.1-era, Arabic fonts
  that relied on a fixed PUA encoding.
- Sinhala script is now shaped by the USE shaper instead of “indic” one.
- Thai shaper improvements.
- hb-ot-name API supports approximate BCP-47 language matching, for example
  asking for “en_US” in a font that has only “en” names will return them.
- Optimized TrueType glyph shape loading.
- Fix subsetting of HarfBuzz faces created via hb_face_create_for_tables().
- Add 32 bit var store support to the subsetter.
- New API
 +HB_BUFFER_FLAG_DEFINED
 +HB_BUFFER_SERIALIZE_FLAG_DEFINED
 +hb_font_changed()
 +hb_font_get_serial()
 +hb_ft_hb_font_changed()
 +hb_set_hash()
 +hb_map_copy()
 +hb_map_hash()

Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>