[Do Not Merge] Update platform security string to 2017-10-01 in KLP dev Bug:64896113 am: f2f5343ba1 am: dafd187ab5 am: 47c92b6200  -s ours
am: bc464d7e8f  -s ours

Change-Id: Iabc705be0af053ce2c3d2e316db03f86e5f61fc5