pgsql: doc: Remove reference to tty libpq connstring param

doc: Remove reference to tty libpq connstring param

The tty connection string parameter was removed in commit 14d9b3760
but the reference to it in the docs was mistakenly kept.  Fix by
removing it from the libpq documentation.  Backpatch through v14
where the parameter was removed.

Author: Noriyoshi Shinoda <noriyoshi.shinoda@hpe.com>
Discussion: https://postgr.es/m/DM4PR84MB173433216FCC2A3961879000EE6B9@DM4PR84MB1734.NAMPRD84.PROD.OUTLOOK.COM
Backpatch-through: 14

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/1d968b87047708eae1d0eef27860668ec318a3ee

Modified Files
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doc/src/sgml/libpq.sgml | 9 ---------
1 file changed, 9 deletions(-)