pgsql: Add missing Assert and fix inaccurate elog message in standby_re

Add missing Assert and fix inaccurate elog message in standby_redo().

All other WAL redo routines either call RestoreBkpBlocks() or Assert that
they haven't been passed any backup blocks. Make this one do likewise.
Also, fix incorrect routine name in its failure message.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/2af72cefeaa15e27277d327783fdec2748d9b758

Modified Files
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src/backend/storage/ipc/standby.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)