Revert "SystemUI: Add double tap to sleep gesture"

This reverts commit e0d1a494a0429909200f904141e04e6f7907a3d9.

Conflicts:
	core/res/res/values/config.xml
	core/res/res/values/slim_symbols.xml

Change-Id: I024a730a1bb8603fdf2dfca92376f4a035ffdcd7