virsh: Require option name for '--pass-fd' argument of 'qemu-monitor-command'
virsh: Require option name for '--pass-fd' argument of 'qemu-monitor-command'

Require the option name for this argument as otherwise a part of the
'cmd' argument will be claimed.

Fixes: 43edde82afb8eb8b808fd985e01898a543a2ffbc
Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>

crobinso/libvirt,zippy2/libvirt,jfehlig/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,jfehlig/libvirt,libvirt/libvirt,olafhering/libvirt,libvirt/libvirt,libvirt/libvirt,crobinso/libvirt,olafhering/libvirt,crobinso/libvirt,libvirt/libvirt,zippy2/libvirt,jfehlig/libvirt,olafhering/libvirt,jfehlig/libvirt,zippy2/libvirt