[API] Make module IPsec(IKE) a java_sdk_library

It was discussed during mainline design review that since module
IPsec(IKE) will be only used by a restricted set of apps, it
should not be in the bootclasspath and should be a
<java_sdk_library>. As a result, it won't expose its API surface
from frameworks/base/api but from ike/api/

This commit:
- Build ike as a java_sdk_library and expose API in ike/api/
- Hide EapAkaPrimeMethodStateMachine and
  EapMsChapV2MethodStateMachine to successfully expose API

Bug: 145995723
Test: build, flash, boot
Test: manually verified APIs exposed in ike/api/ are the same as
      the APIs that get removed from frameworks/base/
Test: atest FramewokrsIkeTests (passed)
Test: m mts && mts-tradefed run mts-ipsec (passed)
Change-Id: Ie546625cf7a252ba927eec7e5ec9398d7b9ae970
Merged-In: Ie546625cf7a252ba927eec7e5ec9398d7b9ae970