Log how long it takes to start more netd components.

This allows us to catch issues such as:

03-27 05:46:16.268   398   398 I Netd    : Registering NetdNativeService: 1005.5ms

Bug: 34873832
Test: bullhead builds, boots
Test: observed log messages on boot
Change-Id: I69a33affa2379a206c6a8d76b481913a248a715d