pgsql: Improve error reporting in opclasscmds.c - Mailing list pgsql-committers

Improve error reporting in opclasscmds.c

This commit improves error reporting introduced by 911e702077.  It puts
argument of errmsg() to the single line for easier grepping source for error
text.  Also it improves wording of errhint().

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/02a5786df24b12c6379ef1b0375b70b8a9fb4925

Modified Files
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src/backend/commands/opclasscmds.c          | 9 ++++-----
src/test/regress/expected/alter_generic.out | 2 +-
2 files changed, 5 insertions(+), 6 deletions(-)