Fix ServiceState.hashCode() bug.

ServiceState currently overrides hashCode() incorrectly. It hashes an
Array field without using Arrays.hashCode(), meaning that the default
Object.hashCode() implementation is used (which is based on the address
of the Array field). This allows equivalent ServiceState instances to
produce different hashes.

Bug: 128609620
Test: atest CtsTelephonyTestCases:ServiceStateTest
Change-Id: I40a7d0b7ebab6d2a1be47ea63a6d223c4c13700b