pgsql: Split hash.h → hash_xlog.h

Split hash.h → hash_xlog.h

Since the hash AM is going to be revamped to have WAL, this is a good
opportunity to clean up the include file a little bit to avoid including
a lot of extra stuff in the future.

Author: Amit Kapila

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8e1e3f958fb3749fe01e9f2473f4554859c685a8

Modified Files
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src/backend/access/hash/hash.c         |  1 +
src/backend/access/rmgrdesc/hashdesc.c |  2 +-
src/backend/access/transam/rmgr.c      |  2 +-
src/bin/pg_xlogdump/rmgrdesc.c         |  2 +-
src/include/access/hash.h              |  6 ------
src/include/access/hash_xlog.h         | 25 +++++++++++++++++++++++++
6 files changed, 29 insertions(+), 9 deletions(-)