EnabledNetworkModePreferenceController Remove AllowedNetworkType

Power manager decision do enable/disable NR by AllowedNetworkType,
and it will effect the PreferredNetworkMode UI. The
PreferredNetworkMode list no 5G item when AllowedNetworkType
disabled.

Bug: 156709797
Test: make RunSettingsRoboTests ROBOTEST_FILTER=\
EnabledNetworkModePreferenceControllerTest  (pass)

Change-Id: I3ab9eca0956c4cce1b79e518942063b681eb96cd