fix a spelling error in comments.

Docker-DCO-1.1-Signed-off-by: Erik Hollensbe <github@hollensbe.org> (github: erikh)
bridge: Wrap a mutex around the portallocation/portmapper dance in AllocatePort.

Docker-DCO-1.1-Signed-off-by: Erik Hollensbe <github@hollensbe.org> (github: erikh)