pgsql: Remove unused function GetOldestWALSendPointer from walsender co

Remove unused function GetOldestWALSendPointer from walsender code.

That unused function was introduced as a sample because synchronous
replication or replication monitoring tools might need it in the future.
Recently commit 989be08 added the function SyncRepGetOldestSyncRecPtr
which provides almost the same functionality for multiple synchronous
standbys feature. So it's time to remove that unused sample function.
This commit does that.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/46d73e0d65eef19e25bb0d31f1e5c23ff40a3444

Modified Files
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src/backend/replication/walsender.c | 41 -------------------------------------
1 file changed, 41 deletions(-)