Check Cellular support before CarrierServiceTest.

CarrierServiceTest currently does not check for Cellular feature support
before running tests that rely on those features to function properly.
Checks are added to verify that Cellular is supported on the device - if
not, then the test exits early.

Bug: 142265632
Test: atest CarrierServiceTest
Change-Id: Idbaf2404a44d7f590656e2fc8fce292ebb18be36
1 file changed