qemu: Introduce qemuBuildSkipController
qemu: Introduce qemuBuildSkipController

Move the non USB implicit controller checks into their own
helper to reduce the cruft in qemuBuildControllerDevCommandLine.

fabianfreyer/libvirt,eskultety/libvirt,libvirt/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,crobinso/libvirt,eskultety/libvirt,andreabolognani/libvirt,jfehlig/libvirt,zippy2/libvirt,libvirt/libvirt,eskultety/libvirt,jardasgit/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,olafhering/libvirt,crobinso/libvirt,jardasgit/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,eskultety/libvirt,zippy2/libvirt,crobinso/libvirt,jardasgit/libvirt,nertpinx/libvirt,andreabolognani/libvirt,libvirt/libvirt,zippy2/libvirt,crobinso/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,jardasgit/libvirt,andreabolognani/libvirt,jfehlig/libvirt,nertpinx/libvirt,jfehlig/libvirt,olafhering/libvirt,libvirt/libvirt,jardasgit/libvirt,eskultety/libvirt,zippy2/libvirt,nertpinx/libvirt,olafhering/libvirt,olafhering/libvirt