elm_config: password mode change should reflect on already running applications.

elm_config: password mode change should reflect on already running applications.

Summary:
When password mode is changed, the change has to reflect on already running
apps as well. config_sub_apply will not be called for an already running app.

Test Plan:
1. 2 running process
2. Change the config value of password last show in one process
3. Check whether the change has reflected in previous process.

Signed-off By: Shilpa Singh<shilpa.singh@samsung.com>

Reviewers: jpeg, cedric, thiepha

Subscribers: govi, rajeshps

Differential Revision: https://phab.enlightenment.org/D4916

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>