[PATCH v4] localedata: Add brh_PK locale for Brahui language [BZ #33952]

Hello,

This is v4 of the Brahui (brh_PK) locale patch.  v3 was sent on
17 May 2026 and has not yet been reviewed.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33952

Brahui is a Dravidian language spoken by approximately 2.8 million
people (2023 Pakistan Census), primarily in Balochistan, Pakistan.
It is the only Dravidian language written in the Perso-Arabic
(Nastaliq) script, with ISO 639-3 code "brh".  I am a native Brahui
speaker, author and translator, and the contributing submitter for
CLDR locale brh.

The full list of changes since v3 is in the commit message.  The main
ones:

- iso-639.def: restored alphabetical order (Brahui before Braj).
- LC_TIME: first_weekday corrected from 7 to 1.  The old value
  selected Saturday; CLDR territory data for PK gives firstDay = sun,
  and ur_PK and sd_PK both use 1.
- LC_TIME: d_t_fmt and date_fmt reordered so the date precedes the
  time, matching the CLDR brh combination pattern and sd_PK, with
  U+060C ARABIC COMMA as the separator.
- LC_TIME: abday now repeats the full day names; Brahui has no
  distinct abbreviated forms and CLDR brh gives identical values at
  both widths, as ur_PK, pa_PK and fa_IR also do.
- LC_MONETARY: n_sep_by_space now matches p_sep_by_space.


Tested with localedef on glibc 2.39.  The only diagnostics are the two
ISO 639 lookups that this patch's iso-639.def hunk resolves; verified
by substituting an already-registered 639-3 code (brx) into the same
file, which compiles with no diagnostics at all.  LC_TIME, LC_COLLATE,
LC_MESSAGES, LC_MONETARY, LC_CTYPE and LC_ADDRESS output verified at
runtime through strftime, strcoll, rpmatch, strfmon, iconv and
nl_langinfo.


CLDR locale brh exists; CLDR ticket CLDR-19285 is accepted for
CLDR 49.

Thanks,
Hammad Mengal