Provide a hook constructor which accepts an ETW provider
Provide a hook constructor which accepts an ETW provider

Previously, the only constructor for the etwlogrus hook accepted a name, and
created a new ETW provider with that name. With this change, there is another
constructor which takes an already created ETW provider. This is to allow the
use of the ETW provider for other things, such as if the application wants to
support ETW capture state.

microsoft/go-winio,Microsoft/go-winio