Branch: b1_4

Branch: b1_4
Revert "last little bit of cleanup" for lli_size_sem locking.  Getting this
lock (a semaphore which can sleep) in ll_nopage and/or ll_ap_refresh_count
causes the client to lock up (symptoms include kupdated stuck, no free mem,
client unresponsive to network = elan timeouts).

Still need to figure proper locking solution here.  A spinlock is good for
all places except for ll_setattr_raw->vmtruncate path.

b=5654 (added under), b=6057, b=6059, b=6077 (possible fix)