ASB February 2018, update security string to 2018-02-01

Implemented patches:
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Media framework
CVE-2017-13228 A-69478425 Critical
CVE-2017-13229 A-68160703 Critical
CVE-2017-13230 A-65483665 Critical
CVE-2017-13232 A-68953950 High
CVE-2017-13233 A-62851602 High
CVE-2017-13234 A-68159767 High
CVE-2017-13235 A-68342866 High
CVE-2017-13241 A-69065651 Moderate

System
CVE-2017-13242 A-62672248 Moderate

HAL
CVE-2017-11041 A-35269676* High

NOT Implemented, because not relevant
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Framework
CVE-2017-13239 A-66244132 Moderate 8.0
CVE-2017-13240 A-68694819 Moderate 8.0, 8.1

Media framework
CVE-2017-13231 A-67962232 High     8.0, 8.1

System
CVE-2017-13236 A-68217699 Moderate 8.0, 8.1
CVE-2017-13243 A-38258991 Moderate (not publicly available)

Change-Id: I91117d71f7c28e3fe05c2a40a5513c66d73c8d4e