Factor out HelpUtils into @SystemAPI lib

This is the first of a few sub-libraries that will get factored out of
the settings lib. These libs will be included by mainline modules which
are compiles against system-api.

Bug: 110953302
Test: Looked at UI
      m -j RunRoboSettingsLibTests
Change-Id: I16347e565aca554d6a8653df35765c2194479e78