pgsql: Don't specify number of dimensions in cases where we don't know

Don't specify number of dimensions in cases where we don't know it.

A few places in array_in() and plperl would report a misleading value
(always MAXDIM+1) for the number of dimensions in the input, because
we'd error out as soon as that was clearly too large rather than
scanning the entire input. There doesn't seem to be much value in
offering the true number, at least not enough to justify the extra
complication involved in trying to get it. So just remove that
parenthetical remark. We already have other places that do it
like that, anyway.

Per suggestions from Alexander Lakhin and Heikki Linnakangas.

Discussion: https://postgr.es/m/2794005.1683042087@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8d5573b92e66075c20f327d93d46a24095739a58

Modified Files
--------------
src/backend/utils/adt/arrayfuncs.c | 8 ++++----
src/pl/plperl/expected/plperl_array.out | 2 +-
src/pl/plperl/plperl.c | 4 ++--
3 files changed, 7 insertions(+), 7 deletions(-)