pgsql: Revert "Prevent incorrect updates of pg_index while reindexing p

Revert "Prevent incorrect updates of pg_index while reindexing pg_index itself."

This reverts commit a03e3e1fd1d4ecfeb1096aeb7854b717061a75d9 of 2011-04-15.
There's a better way to do it, which will follow shortly.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/1da9966230a30405ea5981403d4f4a9d83cb1ecb

Modified Files
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src/backend/catalog/index.c |   28 ++++------------------------
1 files changed, 4 insertions(+), 24 deletions(-)