travis: Remove usage of 'sudo'
travis: Remove usage of 'sudo'

Travis CI reports

  root: deprecated key sudo (The key `sudo` has no effect anymore.)

so let's drop it.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>
Reviewed-by: Daniel P. Berrangé <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>

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