pgsql: Reject nonzero day fields in AT TIME ZONE INTERVAL functions.

Reject nonzero day fields in AT TIME ZONE INTERVAL functions.

It's not sensible for an interval that's used as a time zone value to be
larger than a day. When we changed the interval type to contain a separate
day field, check_timezone() was adjusted to reject nonzero day values, but
timetz_izone(), timestamp_izone(), and timestamptz_izone() evidently were
overlooked.

While at it, make the error messages for these three cases consistent.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9afc58396af75d59ea2eec467724faf68fe63890

Modified Files
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src/backend/utils/adt/date.c | 4 ++--
src/backend/utils/adt/timestamp.c | 8 ++++----
2 files changed, 6 insertions(+), 6 deletions(-)