pgsql: Avoid unnecessary public struct declaration in slru.h

Avoid unnecessary public struct declaration in slru.h

Instead, declare a public wrapper of the sole function using it for
external callers, so that they don't have to always pass a NULL
argument.

Author: Kevin Grittner

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=55573990cac93d9f17a5c3ef19946415f8244903

Modified Files
--------------
src/backend/access/transam/clog.c | 4 ++--
src/backend/access/transam/multixact.c | 8 ++++----
src/backend/access/transam/slru.c | 24 +++++++++++++++++++-----
src/backend/access/transam/subtrans.c | 2 +-
src/backend/commands/async.c | 2 +-
src/include/access/slru.h | 5 +----
6 files changed, 28 insertions(+), 17 deletions(-)