Show/hide 5G preferred network type also consider allowed_network_type

1. The carrier or privileged apps will enable/disable network types on
the device, so Settings references the allowed network type to show/hide
5G preferred network type option.

2. For mainline, copy the getNetworkTypeFromRaf() from RadioFamily to
Settings.

Bug: 136730709
Test: Manual test & EnabledNetworkModePreferenceControllerTest
1. Enable allowed_network_type
2. Disable allowed_network_type
Change-Id: I493f2a2c7f4bc32b3fcb8ab2bace5839d8667bd5