pgsql: Add LZ4 compression to pg_dump

Add LZ4 compression to pg_dump

Expand pg_dump's compression streaming and file APIs to support the lz4
algorithm. The newly added compress_lz4.{c,h} files cover all the
functionality of the aforementioned APIs. Minor changes were necessary
in various pg_backup_* files, where code for the 'lz4' file suffix has
been added, as well as pg_dump's compression option parsing.

Author: Georgios Kokolatos
Reviewed-by: Michael Paquier, Rachel Heaton, Justin Pryzby, Shi Yu, Tomas Vondra
Discussion: https://postgr.es/m/faUNEOpts9vunEaLnmxmG-DldLSg_ql137OC3JYDmgrOMHm1RvvWY2IdBkv_CRxm5spCCb_OmKNk2T03TMm0fBEWveFF9wA1WizPuAgB7Ss%3D%40protonmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0da243fed0875932f781aff08df782b56af58d02

Modified Files
--------------
doc/src/sgml/ref/pg_dump.sgml | 13 +-
src/bin/pg_dump/Makefile | 2 +
src/bin/pg_dump/compress_io.c | 26 +-
src/bin/pg_dump/compress_lz4.c | 626 ++++++++++++++++++++++++++++++++++
src/bin/pg_dump/compress_lz4.h | 24 ++
src/bin/pg_dump/meson.build | 8 +-
src/bin/pg_dump/pg_backup_archiver.c | 6 +-
src/bin/pg_dump/pg_backup_directory.c | 9 +-
src/bin/pg_dump/pg_dump.c | 5 +-
src/bin/pg_dump/t/002_pg_dump.pl | 82 ++++-
src/tools/pginclude/cpluspluscheck | 1 +
src/tools/pgindent/typedefs.list | 2 +
12 files changed, 782 insertions(+), 22 deletions(-)