pgsql: Talk about assigning, rather than generating, new MultiXactIds.

Talk about assigning, rather than generating, new MultiXactIds.

The word "assign" is used in various places internally to describe what
GetNewMultiXactId does, but the user-facing messages have previously
said "generate". For consistency, standardize on "assign," which seems
(at least to me) to be slightly clearer.

Discussion: http://postgr.es/m/CA+TgmoaoE1_i3=4-7GCTtKLVZVQ2Gh6qESW2VG1OprtycxOHMA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a1a5da8cb74b7abf54a1f5fc5b5a442bb807843c

Modified Files
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src/backend/access/transam/multixact.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)