pgsql: Fix CVE-2013-0255 properly.

Fix CVE-2013-0255 properly.

Revert commit ab0f7b6089fd215f6ce6081e2e222c38d643a526 (in HEAD only)
in favor of the proper solution, which is to declare enum_recv() correctly
in the system catalogs.  It should be declared to take type "internal"
not "cstring".

Also improve the type_sanity regression test, which should have caught
this typo, so that it actually would.  Most of the relevant checks on
the signature of type I/O functions should not have been restricted to
basetypes/pseudotypes, as they should apply to any type's I/O functions.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/71627f3d1964ef9831ea7997d2f4ac5617c718cc

Modified Files
--------------
src/backend/utils/adt/enum.c              |    5 -----
src/include/catalog/catversion.h          |    2 +-
src/include/catalog/pg_proc.h             |    2 +-
src/test/regress/expected/type_sanity.out |   16 ++++++++++------
src/test/regress/sql/type_sanity.sql      |   16 ++++++++++------
5 files changed, 22 insertions(+), 19 deletions(-)