pgsql: Use LOCKMODE in parse_relation.c/.h

Use LOCKMODE in parse_relation.c/.h

There were a couple of comments in parse_relation.c

> Note: properly, lockmode should be declared LOCKMODE not int, but that
> would require importing storage/lock.h into parse_relation.h. Since
> LOCKMODE is typedef'd as int anyway, that seems like overkill.

but actually LOCKMODE has been in storage/lockdefs.h for a while,
which is intentionally a more narrow header. So we can include that
one in parse_relation.h and just use LOCKMODE normally.

An alternative would be to add a duplicate typedef into
parse_relation.h, but that doesn't seem necessary here.

Reviewed-by: Andreas Karlsson <andreas(at)proxel(dot)se>
Reviewed-by: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/4bcd65fb-2497-484c-bb41-83cb435eb64d%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/aca61f7e5f8a8a96865d33d0a6f993bf346f47db

Modified Files
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src/backend/parser/parse_relation.c | 12 ++----------
src/include/parser/parse_relation.h | 5 +++--
2 files changed, 5 insertions(+), 12 deletions(-)