pgsql: Replace float8 with int in date2isoweek() and date2isoyear().

Replace float8 with int in date2isoweek() and date2isoyear().

The values of the "result" variables in these functions are
always integers; using a float8 variable accomplishes nothing
except to incur useless conversions to and from float. While
that wastes a few nanoseconds, these functions aren't all that
time-critical. But it seems worth fixing to remove possible
reader confusion.

Also, in the case of date2isoyear(), "result" is a very poorly
chosen variable name because it is *not* the function's result.
Rename it to "week", and do the same in date2isoweek() for
consistency.

Since this is mostly cosmetic, there seems little need
for back-patch.

Author: Sergey Fukanchik <s(dot)fukanchik(at)postgrespro(dot)ru>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/6323a-68726500-1-7def9d00@137821581

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/84ce2587075c9418deda6a2f04b9768e375ebe43

Modified Files
--------------
src/backend/utils/adt/timestamp.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)