dhcp: nettools: drop the 'iface' parameter when no more used

Drop it from the functions for extracting the dhcp options from the
lease: it was just used for the logging, but now we log all the options
once, at the end of the process.
17 jobs for fg/nettools_dhcp_options_II in 37 minutes and 58 seconds (queued for 10 seconds)
Status Job ID Name Coverage
  Test
passed #518321
allowed to fail
checkpatch

00:01:11

manual #518326
allowed to fail manual
t_centos:7.5.1804
passed #518327
t_centos:7.6.1810

00:27:02

passed #518333
t_debian:10

00:20:53

passed #518332
t_debian:9

00:25:10

passed #518335
t_debian:sid

00:25:16

manual #518334
allowed to fail manual
t_debian:testing
passed #518322
t_fedora:28

00:32:29

passed #518323
t_fedora:29

00:37:21

passed #518324
t_fedora:30

00:27:59

manual #518325
allowed to fail manual
t_fedora:rawhide
passed #518328
t_ubuntu:16.04

00:13:17

passed #518329
t_ubuntu:18.04

00:17:59

manual #518331
allowed to fail manual
t_ubuntu:devel
manual #518330
allowed to fail manual
t_ubuntu:rolling
 
  External
failed https://desktopqe-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/job/beaker-NetworkManager-gitlab-trigger-code-upstream/597/

failed https://desktopqe-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/job/beaker-NetworkManager-gitlab-trigger-code-upstream/597/

00:05:29