Align kernel args for system upgrade using leapp

leapp is looking for errors in /etc/default/grub and
fixes it during upgrade. It does not recognize entries
starting other than "GRUB", as tripleo sets the entry
starting with TRIPLEO_ instead of GRUB, append the
entry with GRUB_ so that leapp upgrades correctly.
Closes-Bug: #1890080
Change-Id: I9238cd35a1114b1649a38ab4f24225865bcecf19

deployment/kernel/kernel-boot-params-baremetal-ansible.yaml

@@ -98,3 +98,23 @@ outputs:
           vars:
             tripleo_kernel_args: {get_attr: [RoleParametersValue, value, kernel_args]}
             tripleo_kernel_reboot_timeout: {get_param: NodeRebootWaitTimeout}
+      upgrade_tasks:
+        - name: upgrade prepare for leapp to align kernel arg shortcommings in leapp
+          tags:
+            - never
+            - system_upgrade
+            - system_upgrade_prepare
+          when:
+            - step|int == 3
+            - upgrade_leapp_enabled
+          block:
+            - name: fix grub entries to have name start with GRUB_
+              replace:
+                path: '/etc/default/grub'
+                regexp: '^(TRIPLEO_HEAT_TEMPLATE_KERNEL_ARGS)(.*)'
+                replace: 'GRUB_\1\2'
+            - name: fix grub entries in append statement
+              replace:
+                path: '/etc/default/grub'
+                regexp: '(.*){(TRIPLEO_HEAT_TEMPLATE_KERNEL_ARGS)}(.*)'
+                replace: '\1{GRUB_\2}\3'