mtp: support windows phones.
mtp: support windows phones.

Windows phones have no mtp in interface string

riwsakiP8/riwsakiza-go-mtpfs,FracturedRetina/go-mtpfs,FracturedRetina/go-mtpfs,cmars/tools,riwsakiP8/riwsakiza-go-mtpfs,cmars/tools,wisavalite/go-mtpfs,wisavalite/go-mtpfs,wisavalite/go-mtpfs,cmars/tools,cmars/tools,riwsakiP8/riwsakiza-go-mtpfs,FracturedRetina/go-mtpfs