pgsql: Remove no-longer-appropriate special case in psql's \conninfo co

Remove no-longer-appropriate special case in psql's \conninfo code.

\conninfo prints the results of PQhost() and some other libpq functions.
It used to override the PQhost() result with the hostaddr parameter if
that'd been given, but that's unhelpful when multiple hosts were listed
in the connection string. Furthermore, it seems unnecessary in the wake
of commit 1944cdc98, since PQhost does any useful substitution itself.
So let's just remove the extra code and print PQhost()'s result without
any editorialization.

Back-patch to v10, as 1944cdc98 (just) was.

Discussion: https://postgr.es/m/23287.1533227021@sss.pgh.pa.us

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d8b2beb269c9606513a1693ac2e21586aa693e1a

Modified Files
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src/bin/psql/command.c | 22 +---------------------
1 file changed, 1 insertion(+), 21 deletions(-)