Revert "led: core: Fix brightness setting when setting delay_off=0"

This reverts commit 20f6d9c2, which
was commit 2b83ff96f51d0b039c4561b9f95c824d7bddb85c upstream.
The bug that it should fix was only introduced in Linux 4.7, and
in 4.4 it causes a regression.

Reported-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: Wang Han <wanghan1995315@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>