Add ANT to the list of toggleable airplane mode radios

Adding ANT to the list of toggleable radios allows ANT to behave in the same way as Wifi or
Bluetooth in regards to operation during airplane mode: when airplane mode is turned on, ANT is
disabled, but can be re-enabled by the user at any time.

Change-Id: Idb9e9499fd7a7fccee8c459779ec86bf24e1373e