pgsql: Remove _hash_chgbufaccess().

Remove _hash_chgbufaccess().

This is basically for the same reasons I got rid of _hash_wrtbuf()
in commit 25216c98938495fd741bf585dcbef45b3a9ffd40: it's not
convenient to have a function which encapsulates MarkBufferDirty(),
especially as we move towards having hash indexes be WAL-logged.

Patch by me, reviewed (but not entirely endorsed) by Amit Kapila.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/7819ba1ef6c5297b7e27878d2b3d30c5bcef8939

Modified Files
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src/backend/access/hash/hash.c | 20 +++++------
src/backend/access/hash/hashinsert.c | 15 +++++----
src/backend/access/hash/hashovfl.c | 32 +++++++++---------
src/backend/access/hash/hashpage.c | 64 +++++++++++++-----------------------
src/backend/access/hash/hashsearch.c | 18 +++++-----
src/include/access/hash.h | 2 --
6 files changed, 66 insertions(+), 85 deletions(-)