pgsql: simplehash: Additional tweaks to make specifying an allocator wo

simplehash: Additional tweaks to make specifying an allocator work.

Even if we don't emit definitions for SH_ALLOCATE and SH_FREE, we
still need prototypes. The user can't define them before including
simplehash.h because SH_TYPE isn't available yet.

For the allocator to be able to access private_data, it needs to
become an argument to SH_CREATE. Previously we relied on callers
to set that after returning from SH_CREATE, but SH_CREATE calls
SH_ALLOCATE before returning.

Dilip Kumar, reviewed by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/72257f95781af97108fa9a9e7224ec81a90e7693

Modified Files
--------------
src/backend/executor/execGrouping.c | 3 +--
src/backend/nodes/tidbitmap.c | 2 +-
src/include/lib/simplehash.h | 10 ++++++++--
3 files changed, 10 insertions(+), 5 deletions(-)