pgsql: Simplify some logic in CreateReplicationSlot()

Simplify some logic in CreateReplicationSlot()

This refactoring reduces the code in charge of creating replication
slots from two "if" block to a single one, making it slightly cleaner.

This change is possible since 1d04a59be31b, that has removed the
intermediate code that existed between the two "if" blocks in charge of
initializing the output message buffer.

Author: Peter Smith
Discussion: https://postgr.es/m/CAHut+PtnJzqKT41Zt8pChRzba=QgCqjtfYvcf84NMj3VFJoKfw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e83aa9f92fdd88c2912cc43a61fd9f59f4c8f4d3

Modified Files
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src/backend/replication/walsender.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)