pgsql: Suppress an uninitialized-variable warning (not all versions of

Log Message:
-----------
Suppress an uninitialized-variable warning (not all versions of gcc
complain here, but some do)

Modified Files:
--------------
pgsql/src/backend/storage/freespace:
freespace.c (r1.63 -> r1.64)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/freespace/freespace.c?r1=1.63&r2=1.64)