Since the requirement is that the area's top cache is locked, allocating
memory isn't allowed.
* lock_memory_etc(): Create the VMAreaWiredRange object explicitly before
locking the area's top cache.
Fixes#5680 (deadlocks when using the slab as malloc() backend).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36033 a95241bf-73f2-0310-859d-f6bbb57e9c96