pgsql: Revert the patch to check if we've reached end-of-backup also wh

Revert the patch to check if we've reached end-of-backup also when doing
crash recovery, and throw an error if not. hubert depesz lubaczewski pointed
out that that situation also happens in the crash recovery following a
system crash that happens during an online backup.

We might want to do something smarter in 9.1, like put the check back for
backups taken with pg_basebackup, but that's for another patch.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/54685b1c2b356b4b9c0938f6b8dcc52e173c0400

Modified Files
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src/backend/access/transam/xlog.c |   36 ++++++++++++++++++++++++++----------
1 files changed, 26 insertions(+), 10 deletions(-)