pgsql: Remove useless/confusing const qualifiers

Remove useless/confusing const qualifiers

The const qualifiers removed here did not qualify what is being
pointed to, which is the normal use in function prototypes. Instead,
they qualify the variable itself, so that it cannot be changed inside
the function. That is itself not wrong, but it's not a normal style,
and it seems distracting here.

Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/c855d318-4545-4dc7-b466-2e24fbf64725%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/370f3366c4c214abb0c34b2e2bd7fd42802112bf

Modified Files
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src/bin/psql/describe.c | 14 +++++++-------
src/fe_utils/print.c | 20 ++++++++++----------
src/include/fe_utils/print.h | 18 +++++++++---------
3 files changed, 26 insertions(+), 26 deletions(-)