Correct issue with ansible hardening and systemd

The systemd command does not have a stable api and can return different
codes when executed. This change converts the task to query the target
unit and disable it if it exists to a single systemd task using the
ansible module.

Closes-Bug: #1787048
Change-Id: I74c43839cd7d3a8620a0fb8e405fbc3f6a0f44d0
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>

tasks/rhel7stig/misc.yml

@@ -36,22 +36,14 @@
     - V-71985
 
 # This returns an exit code of 0 if it's running, 3 if it's masked.
-- name: Check if ctrl-alt-del.target is already masked
-  command: systemctl status ctrl-alt-del.target
-  register: cad_mask_check
-  check_mode: no
-  changed_when: False
-  failed_when: cad_mask_check.rc not in [0,3]
-  tags:
-    - always
-
 - name: V-71993 - The x86 Ctrl-Alt-Delete key sequence must be disabled
-  command: systemctl mask ctrl-alt-del.target
+  systemd:
+    name: ctrl-alt-del.target
+    enabled: no
+    masked: yes
+    daemon_reload: yes
   when:
     - security_rhel7_disable_ctrl_alt_delete | bool
-    - cad_mask_check.rc != 3
-  notify:
-    - reload systemd
   tags:
     - high
     - misc