[Sat] Update device-based carrier string

Previously, the text was "Connected to satellite" / "Not connected to
satellite". Now we show a single "Satellite SOS" carrier text when the
radio is on, despite its current connection state.

Test: DeviceBasedSatelliteViewModelTest
Test: manual via demo mode
Bug: 336293844
Flag: ACONFIG com.android.internal.telephony.flags.oem_enabled_satellite_flag NEXTFOOD
Change-Id: I281baf8bd721c5259aa4c88ac9e96efa60536e17