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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master

Details
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https://git.postgresql.org/pg/commitdiff/40ca9073ff228163b1320122a82e4064da6cf54f

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