Revert "[1/2] Setting: Lockscreen maximized widgets"

This reverts commit fb74dc508aee3fd930aa233a02640d3ad1cd70ae.
[1/2] Setting: Lockscreen maximized widgets

Settings part of maximizing lockscreen widgets

Modified from CM
Settings: Add max widget to rest of lockscreens
security: fix FC for security option

If device is a low-memory one then the key_enable_widget dependency can't be removed.
So, move the logic to disable maximize widget feature for low-memory devices.