pgsql: Prohibit identity columns on typed tables and partitions

Prohibit identity columns on typed tables and partitions

Those cases currently crash and supporting them is more work then
originally thought, so we'll just prohibit these scenarios for now.

Author: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Reported-by: Мансур Галиев <gomer94@yandex.ru>
Bug: #14866

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/005ac298b1bdc3e9bd19e5ee2bcf7e320ebe4130

Modified Files
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src/backend/parser/parse_utilcmd.c     | 13 +++++++++++++
src/test/regress/expected/identity.out | 12 ++++++++++++
src/test/regress/sql/identity.sql      | 16 ++++++++++++++++
3 files changed, 41 insertions(+)