pgsql: Remove explicit error handling for obsolete date/time values

Remove explicit error handling for obsolete date/time values

The date/time values 'current', 'invalid', and 'undefined' were
removed a long time ago, but the code still contains explicit error
handling for the transition. To simplify the code and avoid having to
handle these values everywhere, just remove the recognition of these
tokens altogether now.

Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/666cbae16da46b833f57ef8b12ff0bf215684d9c

Modified Files
--------------
src/backend/utils/adt/date.c | 8 --------
src/backend/utils/adt/datetime.c | 20 --------------------
src/backend/utils/adt/timestamp.c | 22 ----------------------
src/include/utils/datetime.h | 2 --
src/interfaces/ecpg/pgtypeslib/dt.h | 2 --
src/interfaces/ecpg/pgtypeslib/dt_common.c | 5 -----
src/interfaces/ecpg/pgtypeslib/timestamp.c | 4 ----
src/test/regress/expected/date.out | 3 ---
src/test/regress/expected/timestamp.out | 13 -------------
src/test/regress/expected/timestamptz.out | 13 -------------
src/test/regress/sql/date.sql | 1 -
src/test/regress/sql/timestamp.sql | 4 ----
src/test/regress/sql/timestamptz.sql | 4 ----
13 files changed, 101 deletions(-)