Stop removing missing /run/nologin in RPM images

This code was valid for centos:8 and centos:stream8, but is not required
for centos:stream9 or rockylinux:9 which do not include this file.

Change-Id: I50f78d73afe0944dd91998ab9799fa2f36cc46a3

Author: priteau

docker/haproxy/haproxy-ssh/Dockerfile.j2

@@ -16,10 +16,6 @@ LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build
         'rsync',
     ] %}
 
-# NOTE(mgoddard): The centos:8 image contains a /run/nologin file, which
-# prevents SSH access to it.
-RUN rm -f /run/nologin
-
 {% elif base_package_type == 'deb' %}
     {% set haproxy_ssh_packages = [
         'openssh-server',

docker/keystone/keystone-ssh/Dockerfile.j2

@@ -15,10 +15,6 @@ LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build
         'rsync'
     ] %}
 
-# NOTE(mgoddard): The centos:8 image contains a /run/nologin file, which
-# prevents SSH access to it.
-RUN rm -f /run/nologin
-
 {% elif base_package_type == 'deb' %}
     {% set keystone_ssh_packages = [
         'openssh-server',

docker/nova/nova-ssh/Dockerfile.j2

@@ -13,13 +13,7 @@ LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build
     'openssh-server'
 ] %}
 
-{% if base_package_type == 'rpm' %}
-
-# NOTE(mgoddard): The centos:8 image contains a /run/nologin file, which
-# prevents SSH access to it.
-RUN rm -f /run/nologin
-
-{% elif base_package_type == 'deb' %}
+{% if base_package_type == 'deb' %}
 
 RUN mkdir -p /var/run/sshd \
     && chmod 0755 /var/run/sshd