Always include BAND_MODE=AUTOMATIC in the Radio Band Mode List

To facilitate user recovery from issues where the band mode
list is incomplete and may not report the full list of bands,
the user should *always* have the ability to set the band mode
selection to AUTOMATIC.

Bug: 28124606
Test: compilation, UI check
Change-Id: Ib961d9b058ade5a51dfec0777971c8c98dee2033
(cherry picked from commit f8555e48)