pgsql: Remove the unused argument of PSQLexec().

Remove the unused argument of PSQLexec().

This commit simply removes the second argument of PSQLexec that was
set to the same value everywhere. Comments and code blocks related
to this parameter are removed.

Noticed by Heikki Linnakangas, reviewed by Michael Paquier

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/efbbbbc8b51bacd32e96c3f747dd6aa4c0e444cb

Modified Files
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src/bin/psql/command.c   |    6 +--
src/bin/psql/common.c    |   21 +--------
src/bin/psql/common.h    |    2 +-
src/bin/psql/describe.c  |  108 +++++++++++++++++++++++-----------------------
src/bin/psql/large_obj.c |   12 +++---
5 files changed, 65 insertions(+), 84 deletions(-)