Thread: pgsql: Fix error message on short read of pg_control

Fix error message on short read of pg_control

Instead of saying "error: success", indicate that we got a working read
but it was too short.

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/714d8e5fa1b21a1113d6cd444af5cbc9d67d566f

Modified Files
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src/backend/access/transam/xlog.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)