pgsql: Code cleanup: in C89, there is no point casting the first

Log Message:
-----------
Code cleanup: in C89, there is no point casting the first argument to
memset() or MemSet() to a char *. For one, memset()'s first argument is
a void *, and further void * can be implicitly coerced to/from any other
pointer type.

Modified Files:
--------------
pgsql/src/backend/access/hash:
hashovfl.c (r1.45 -> r1.46)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/hash/hashovfl.c.diff?r1=1.45&r2=1.46)
hashpage.c (r1.48 -> r1.49)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/hash/hashpage.c.diff?r1=1.48&r2=1.49)
hashutil.c (r1.41 -> r1.42)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/hash/hashutil.c.diff?r1=1.41&r2=1.42)
pgsql/src/backend/storage/lmgr:
lock.c (r1.150 -> r1.151)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/lmgr/lock.c.diff?r1=1.150&r2=1.151)
pgsql/src/backend/utils/cache:
relcache.c (r1.222 -> r1.223)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/cache/relcache.c.diff?r1=1.222&r2=1.223)
syscache.c (r1.98 -> r1.99)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/cache/syscache.c.diff?r1=1.98&r2=1.99)
pgsql/src/backend/utils/fmgr:
dfmgr.c (r1.79 -> r1.80)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/fmgr/dfmgr.c.diff?r1=1.79&r2=1.80)
pgsql/src/include:
c.h (r1.182 -> r1.183)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/c.h.diff?r1=1.182&r2=1.183)
pgsql/src/interfaces/libpq:
fe-protocol2.c (r1.16 -> r1.17)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-protocol2.c.diff?r1=1.16&r2=1.17)