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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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/fbc56f706cdadaaf2a686dacece8b403dfaef50b

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