staging: protect important apps' priorities
lmk: avoid null pointer dereference
row: adapt to 2.6.39 core
workqueue: implement WQ_NON_REENTRANT

With gcwq managing all the workers and work->data pointing to the last
gcwq it was on, non-reentrance can be easily implemented by checking
whether the work is still running on the previous gcwq on queueing.
Implement it.

Signed-off-by: Tejun Heo <tj@kernel.org>
workqueue: bring inline with 18aa9ef
row: remove missing flags
config: update defconfigs