pgsql: Add a new option to RestoreBkpBlocks() to indicate if a cleanup

Log Message:
-----------
Add a new option to RestoreBkpBlocks() to indicate if a cleanup lock should
be used instead of the normal exclusive lock, and make WAL redo functions
responsible for calling RestoreBkpBlocks(). They know better what kind of a
lock they need.

At the moment, this just moves things around with no functional change, but
makes the hot standby patch that's under review cleaner.

Modified Files:
--------------
pgsql/src/backend/access/gin:
ginxlog.c (r1.16 -> r1.17)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginxlog.c?r1=1.16&r2=1.17)
pgsql/src/backend/access/gist:
gistxlog.c (r1.31 -> r1.32)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistxlog.c?r1=1.31&r2=1.32)
pgsql/src/backend/access/heap:
heapam.c (r1.273 -> r1.274)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/heap/heapam.c?r1=1.273&r2=1.274)
pgsql/src/backend/access/nbtree:
nbtxlog.c (r1.53 -> r1.54)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/nbtree/nbtxlog.c?r1=1.53&r2=1.54)
pgsql/src/backend/access/transam:
clog.c (r1.51 -> r1.52)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/clog.c?r1=1.51&r2=1.52)
multixact.c (r1.29 -> r1.30)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/multixact.c?r1=1.29&r2=1.30)
xact.c (r1.271 -> r1.272)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/xact.c?r1=1.271&r2=1.272)
xlog.c (r1.327 -> r1.328)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/xlog.c?r1=1.327&r2=1.328)
xlogutils.c (r1.66 -> r1.67)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/xlogutils.c?r1=1.66&r2=1.67)
pgsql/src/backend/catalog:
storage.c (r1.4 -> r1.5)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/storage.c?r1=1.4&r2=1.5)
pgsql/src/backend/commands:
dbcommands.c (r1.217 -> r1.218)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/dbcommands.c?r1=1.217&r2=1.218)
sequence.c (r1.156 -> r1.157)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/sequence.c?r1=1.156&r2=1.157)
tablespace.c (r1.59 -> r1.60)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/tablespace.c?r1=1.59&r2=1.60)
pgsql/src/backend/storage/freespace:
freespace.c (r1.71 -> r1.72)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/freespace/freespace.c?r1=1.71&r2=1.72)
pgsql/src/include/access:
xlog.h (r1.89 -> r1.90)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/access/xlog.h?r1=1.89&r2=1.90)