controller.loadIPAMDriver: Unwrap error type returned by PluginGetter
controller.loadIPAMDriver: Unwrap error type returned by PluginGetter

moby/moby commit b27f70d45 wraps the ErrNotFound error returned when
a plugin cannot be found, to include a backtrace.   This changes the
type of the error, so contoller.loadIPAMDriver no longer converts it
to a libnetwork plugin.NotFoundError.

This is a similar patch as was merged in 9b114971e53b2ee3a917dc20346e869bf4e432e7

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

moby/moby,moul/docker,bearstech/moby,yosifkit/docker,flavio/docker,jameszhan/docker,yosifkit/docker,flavio/docker,yosifkit/docker,thaJeztah/docker,bearstech/moby,jimjag/docker,moul/docker,konstruktoid/docker-upstream,djs55/docker,moby/moby,AkihiroSuda/docker,vdemeester/docker,djs55/docker,jthelin/docker,docker/docker,jameszhan/docker,moby/moby,jimjag/docker,konstruktoid/docker-upstream,cpuguy83/docker,AkihiroSuda/docker,Ramzec/docker,moul/docker,vdemeester/docker,cpuguy83/docker,bearstech/moby,yosifkit/docker,gnailuy/docker,konstruktoid/docker-upstream,jimjag/docker,mahak/docker,gnailuy/docker,thaJeztah/docker,jthelin/docker,trebonian/docker,paralin/docker,Ramzec/docker,jimjag/docker,trebonian/docker,flavio/docker,paralin/docker,djs55/docker,Ramzec/docker,docker/docker,konstruktoid/docker-upstream,nalind/docker,docker/docker,Mokolea/docker,bearstech/moby,Mokolea/docker,jameszhan/docker,mahak/docker,moul/docker,Mokolea/docker,gnailuy/docker,nawawi/docker,nawawi/docker,flavio/docker,Ramzec/docker,nawawi/docker,Mokolea/docker,gnailuy/docker,moby/moby,thaJeztah/docker,AkihiroSuda/docker,paralin/docker,vdemeester/docker,paralin/docker,cpuguy83/docker,cpuguy83/docker,mahak/docker,nalind/docker,thaJeztah/docker,trebonian/docker,nawawi/docker,nalind/docker,trebonian/docker,AkihiroSuda/docker,nalind/docker,mahak/docker