igbvf: Refactor traces

Refactoring "PF still resetting" and changing "Failed
 to add vlan id" to "Vlan id is not added"
messages because previous version looked like a bug
- it informed about changes that worked as
designed but might confuse users

Signed-off-by: Karen Sornek <karen.sornek@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>