[Sat] Split out icon levels in mobile interactor

`MobileIconInteractor.shownLevel` incporporates more specific
information about cellular levels than the satellite icon cares about.
Mainly, if the `INFLATE_SIGNAL_STRENGTH` carrier config is set, then the
satellite icon actually wraps around to default behavior, since a level
of 5 is not defined in the signal icon model.

Fixes: 346904529
Flag: com.android.internal.telephony.flags.oem_enabled_satellite_flag
Test: MobileIconInteractorTest
Test: MobileIconViewModelTest
Change-Id: I2d538bfc0dc1d38a55fd35d2c7875aa3c9072d6e