Fix horizontal spacing in PS Header

1. Removes padding between settings cog and lock button,
as the insets already provide the required padding.
2. Reduces the lock button margin from left to accomodate
the inbuilt inset in the button.

Fix: 336510036
Test: Verified on device.
Flag: NA
Change-Id: I077097c7beb2cc8fe14f4367c66ca4e1ad4270d0