pgsql: Clarify a foreign key error message

Clarify a foreign key error message

Clarify the message about type mismatch in foreign key definition to
indicate which column the referencing and which is the referenced one.

Reported-by: Jian He <jian.universality@gmail.com>
Discussion: /messages/by-id/CACJufxEL82ao-aXOa=d_-Xip0bix-qdSyNc9fcWxOdkEZFko8w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d7a2b5bd8718a6207fb364318d7f7cccdf6219c3

Modified Files
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src/backend/commands/tablecmds.c | 2 +-
src/test/regress/expected/alter_table.out | 16 ++++----
src/test/regress/expected/enum.out | 2 +-
src/test/regress/expected/foreign_key.out | 52 +++++++++++++-------------
src/test/regress/expected/without_overlaps.out | 6 +--
5 files changed, 39 insertions(+), 39 deletions(-)