Convert getBands() to int[] from List<Integer>

To conform with API council guidelines, convert the
getBands() function to store and return an array of
int[] rather than a List<Integer> to avoid autoboxing.

Also:
-Add bands to hashCode() and equals() for CellIdentityLte
-Add EARFCN to hashCode() for CellIdentityLte

Bug: 150399894
Test: atest FrameworksTelephonyTests
Change-Id: I7edd5896b48794cd9c291788c28420ce40898f77