Linux 2.6.39 compat, DEFINE_SPINLOCK()

Linux 2.6.39 compat, DEFINE_SPINLOCK()

This is a long over due compatibility change.  Way, way, way back
in 2007 there was a push to remove all consumers of SPIN_LOCK_UNLOCKED.
Finally, in 2011 with 2.6.39 all the consumers have been updated
and SPIN_LOCK_UNLOCKED was removed.  It's about time we use the
new API as well, this change does exactly that.  DEFINE_SPINLOCK()
was available as far back as 2.6.12 so there doesn't need to be
any additional autoconf-foo for this change.