spec: Enable the iscsi-direct storage driver conditionally
spec: Enable the iscsi-direct storage driver conditionally

Most distributions we build RPMs on don't ship a
recent enough version of libiscsi, so we can't enable
the driver unconditionally. Add an explicit dependency
on the runtime package while at it.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>
Reviewed-by: Pavel Hrdina <d4772d05997b8abf035041e3b4f4996380ea7e7a@redhat.com>

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