[1/2] Add lockscreen rotation as an optional rotation setting

Taken fom:

https://github.com/gokussjx/cm_packages_apps_Settings/commit/a83ae47e184a778ca3067416c56901da70c1bc27

PS7
fixed value handling
PS8
Fix option doesn't stick

Change-Id: I3fd1d2c31d83230d480a0027cb7bf5fcf2db5cb7