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_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ac222a3c374080f241936d2e47149d01ea006d6d

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