pgsql: Assert that buffers are marked dirty before XLogRegisterBuffer()

Assert that buffers are marked dirty before XLogRegisterBuffer().

Enforce the rule from transam/README in XLogRegisterBuffer(), and
update callers to follow the rule.

Hash indexes sometimes register clean pages as a part of the locking
protocol, so provide a REGBUF_NO_CHANGE flag to support that use.

Discussion: https://postgr.es/m/c84114f8-c7f1-5b57-f85a-3adc31e1a904@iki.fi
Reviewed-by: Heikki Linnakangas

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/00d7fb5e2e39198387ae00af8dd18b787b6a4d63

Modified Files
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src/backend/access/gin/ginbtree.c | 14 ++++----
src/backend/access/gin/gindatapage.c | 6 ++++
src/backend/access/gin/ginentrypage.c | 3 ++
src/backend/access/gin/ginfast.c | 5 +--
src/backend/access/hash/hash.c | 11 ++++--
src/backend/access/hash/hashovfl.c | 21 ++++++++----
src/backend/access/transam/xloginsert.c | 16 ++++++++-
src/backend/storage/buffer/bufmgr.c | 59 +++++++++++++++++++++++++++++++++
src/include/access/xloginsert.h | 1 +
src/include/storage/bufmgr.h | 2 ++
10 files changed, 118 insertions(+), 20 deletions(-)