shill: Pass groups to RtnlHandler.Start

Allow clients of the RtnlHandler to explicitly define which groups
they want to listen to. This will allow more flexibility in the clients
without causing everyone to have to listen to all groups.

BUG=none
TEST=FEATURES=test emerge-$BOARD apmanager shill

Change-Id: I2682f6bcfda3a50dade2d1a2b34a2bc1254d7fde
Reviewed-on: https://chromium-review.googlesource.com/265460
Reviewed-by: Nathan Bullock <nathanbullock@google.com>
Commit-Queue: Nathan Bullock <nathanbullock@google.com>
Tested-by: Nathan Bullock <nathanbullock@google.com>
1 file changed