pgsql: Fix bug introduced by the recent patch to check that the checkpo

Fix bug introduced by the recent patch to check that the checkpoint redo
location read from backup label file can be found: wasShutdown was set
incorrectly when a backup label file was found.

Jeff Davis, with a little tweaking by me.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=542bdb2146327972545630d0a428e1c9367266cb

Modified Files
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src/backend/access/transam/xlog.c |    4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)