distro, flock: Adjust package lists for iproute update

This commit adds a build dependency (iptables-devel-1.4.21) for the
iproute package to the distro layer's package list. iproute is
uprevisioned in the distro layer to support IPv6 segment routing, with
change I6de9659dfec830f954661a0b0f82e69dc9637a5d.

In addition, given that iproute will be uprevisioned, this commit also
removes iproute from the distro and flock layers' pre-requisite/chroot
package lists.

Verification:
- Updated iproute package was confirmed to build as expected with this
  commit in a monolithic StarlingX build environment.
- In a layered StarlingX build environment, the distro layer and the
  flock layer were successfully built with this commit and the
  aforementioned iproute uprevisioning companion commit, and an ISO
  image was generated.

Story: 2008921
Task: 43663

Signed-off-by: M. Vefa Bicakci <vefa.bicakci@windriver.com>
Change-Id: I5e272dc59b8b69611474706c165644a8dd5d7f52

centos-mirror-tools/config/centos/distro/rpms_centos.lst

@@ -320,8 +320,8 @@ hmaccalc-0.9.13-4.el7.x86_64.rpm
 hwdata-0.252-9.1.el7.x86_64.rpm
 # info-5.1-5.el7.x86_64.rpm provided by mock
 intltool-0.50.2-7.el7.noarch.rpm
-iproute-4.11.0-14.el7.x86_64.rpm
 iptables-1.4.21-28.el7.x86_64.rpm
+iptables-devel-1.4.21-28.el7.x86_64.rpm
 iputils-20160308-10.el7.x86_64.rpm
 iscsi-initiator-utils-6.2.0.874-10.el7.x86_64.rpm
 iscsi-initiator-utils-iscsiuio-6.2.0.874-10.el7.x86_64.rpm

centos-mirror-tools/config/centos/flock/rpms_centos.lst

@@ -308,7 +308,6 @@ ipa-pgothic-fonts-003.03-5.el7.noarch.rpm
 ipa-pmincho-fonts-003.03-5.el7.noarch.rpm
 iperf3-3.1.7-2.el7.x86_64.rpm
 ipmitool-1.8.18-9.el7_7.x86_64.rpm
-iproute-4.11.0-14.el7.x86_64.rpm
 ipset-6.38-3.el7_6.x86_64.rpm
 ipset-libs-6.38-3.el7_6.x86_64.rpm
 iptables-1.4.21-28.el7.x86_64.rpm