pgsql: Allow NetBSD, m64k to compile the ASM spinlock code.

Log Message:
-----------
Allow NetBSD, m64k to compile the ASM spinlock code.

R?mi Zara

Modified Files:
--------------
pgsql/src/backend/storage/lmgr:
s_lock.c (r1.32 -> r1.33)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/lmgr/s_lock.c.diff?r1=1.32&r2=1.33)