pgsql: ProcessIncomingNotify *must* reset notifyInterruptOccurred when

ProcessIncomingNotify *must* reset notifyInterruptOccurred when called.

This was broken in 9.0 by careless addition of an early-exit path.
Bug report and diagnosis by Jeff Davis.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=c825a15700907d6a155511d82bcf8fe0f2f7dc0b

Modified Files
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src/backend/commands/async.c |    7 ++++---
1 files changed, 4 insertions(+), 3 deletions(-)