pgsql: Always treat a standby returning an an invalid flush location as

Always treat a standby returning an an invalid flush location as async

This ensures that a standby such as pg_receivexlog will not be selected
as sync standby - which would cause the master to block waiting for
a location that could never happen.

Fujii Masao

Branch
------
REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/b8aca12d77612007ebde22db14e3971ef664d553

Modified Files
--------------
src/backend/replication/syncrep.c     |    9 ++++++---
src/backend/replication/walreceiver.c |    5 +++++
src/backend/replication/walsender.c   |   11 +++++++++--
3 files changed, 20 insertions(+), 5 deletions(-)