DataUsagePreferenceController use DataUsageLib before, and DataUsageLib
and com.android.settingslib.net.DataUsageUtils has same functionality.
com.android.settingslib.net.DataUsageUtils will be clean up, so use
DataUsageLib again.
Bug: 286082055
Test: m Settings
Change-Id: I6227f973ec38e5b0520f54a41ac2ede2929a1bcc