leds: lp5523: fix circular locking

Driver contained possibility for circular locking.

One lock is held by sysfs-core and another one by the driver itself.  This
happened when the driver created or removed sysfs entries dynamically.
There is no real need to do those operations.  Now all the sysfs entries
are created at probe and removed at removal.  Engine load and mux
configuration sysfs entries are now visible all the time.  However, access
to the entries fails if the engine is disabled or running.

Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Reviewed-by: Ilkka Koskinen <ilkka.koskinen@nokia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>