wifi: Use new API for data usage function

For mobile, a old API: buildTemplateMobileAll doesn't includes the
merged wifi network, call the new API: buildTemplateCarrierMetered
to replace the old one.

PS: Not only usage functionality but also apply to network policy
control since the default policy is changing to use
new API: buildTemplateCarrier now.

Test: make RunSettingsRoboTests ROBOTEST_FILTER=SettingsDumpServiceTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageLibTest
Test: Manual Test, modify the mobile usage warming and limit bytes and
      check the data via adb shell dumpsys netpolicy

Bug: 176396812
Merged-In: I6fbec14e7be4dc4b5c2fd3659a801521c81b233c
Change-Id: I6fbec14e7be4dc4b5c2fd3659a801521c81b233c