pgsql: Shut down WAL receiver if it's still running at end of recovery.

Shut down WAL receiver if it's still running at end of recovery. We used to
just check that it's not running and PANIC if it was, but that can rightfully
happen if recovery stops at recovery target.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a0c8514149de92d48a8cf0f1a1458486851980a4

Modified Files
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src/backend/access/transam/xlog.c |    9 ++++-----
1 files changed, 4 insertions(+), 5 deletions(-)