pgsql: Remove now-dead code for !HAVE_INT64_TIMESTAMP.

Remove now-dead code for !HAVE_INT64_TIMESTAMP.

This is a basically mechanical removal of #ifdef HAVE_INT64_TIMESTAMP
tests and the negative-case controlled code.

Discussion: https://postgr.es/m/26788.1487455319@sss.pgh.pa.us

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b9d092c962ea3262930e3c31a8c3d79b66ce9d43

Modified Files
--------------
contrib/btree_gist/btree_time.c | 8 -
contrib/btree_gist/btree_ts.c | 8 -
contrib/btree_gist/btree_utils_num.h | 7 -
src/backend/commands/variable.c | 4 -
src/backend/utils/adt/date.c | 250 +------------
src/backend/utils/adt/datetime.c | 110 +-----
src/backend/utils/adt/formatting.c | 24 +-
src/backend/utils/adt/misc.c | 5 -
src/backend/utils/adt/nabstime.c | 12 -
src/backend/utils/adt/rangetypes.c | 10 -
src/backend/utils/adt/selfuncs.c | 18 -
src/backend/utils/adt/timestamp.c | 458 +-----------------------
src/backend/utils/misc/guc.c | 4 -
src/bin/pg_basebackup/streamutil.c | 8 +-
src/bin/pg_waldump/compat.c | 9 -
src/include/datatype/timestamp.h | 51 +--
src/include/utils/date.h | 26 +-
src/include/utils/datetime.h | 10 +-
src/include/utils/timestamp.h | 34 +-
src/interfaces/ecpg/include/pgtypes_interval.h | 4 -
src/interfaces/ecpg/include/pgtypes_timestamp.h | 5 -
src/interfaces/ecpg/pgtypeslib/datetime.c | 5 -
src/interfaces/ecpg/pgtypeslib/dt.h | 40 +--
src/interfaces/ecpg/pgtypeslib/dt_common.c | 80 +----
src/interfaces/ecpg/pgtypeslib/interval.c | 54 ---
src/interfaces/ecpg/pgtypeslib/timestamp.c | 82 -----
26 files changed, 28 insertions(+), 1298 deletions(-)