pgsql: Use separate lwlock tranches for buffer, lock, and predicate loc

Use separate lwlock tranches for buffer, lock, and predicate lock managers.

This finishes the work - spread across many commits over the last
several months - of putting each type of lock other than the named
individual locks into a separate tranche.

Amit Kapila

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c319991bcad02a2e99ddac3f42762b0f6fa8d52a

Modified Files
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src/backend/storage/lmgr/lwlock.c | 146 +++++++++++++++++++++++++++-----------
src/include/storage/lwlock.h      |   3 +
2 files changed, 106 insertions(+), 43 deletions(-)