[DO NOT MERGE] Update platform security string to 2017-10-01 in lmp-dev...

[DO NOT MERGE] Update platform security string to 2017-10-01 in lmp-dev Bug:64896113 am: cf83f5a4  -s ours am: b40465ed am: acc7e47f  -s ours am: 286c80e9 am: 3b9a25dc am: 9f7048b3 am: 7c50949d  -s ours am: 595b11f9 am: dc48c433 am: 3dd51fb9 am: 223d5971 am: 19709747  -s ours am: 0693cd36 am: 9f76abf9
am: 4507de1d

Change-Id: Id52e163de28340a138ca002be34c1e53706e6e6a