Fix acpi-call-dkms

This fixes `acpi-call-dkms` that was [broken on hwe-edge kernels](https://bugs.launchpad.net/ubuntu/+source/acpi-call/+bug/1724862/comments/3).

Make sure you have a _hardware enablement_ (hwe) kernel installed - e.g. 4.13 - and apply this fix.

If you haven't already, manually install `shim-signed` first:

```
sudo apt update && sudo apt install shim-signed
```

Now apply this fix:

```
sudo env ANSIBLE_NOCOWS=1 ansible-playbook x1yoga.yml --tags tlp
```

If you haven't ran or installed `shim-signed` manually, ansible will crash the first time because it cannot be installed this dependency unattended.

If this happens, run:

```
sudo dpkg --configure -a
```

Enter a secure boot password, reboot, and re-type the password on boot.

roles/packages/tasks/tlp.yml

@@ -1,11 +1,17 @@
 ---
 - name: TLP Power Management | Add Repository
-  tags: [x1yoga,system]
+  tags: [x1yoga,system,tlp]
   apt_repository:
     repo: ppa:linrunner/tlp
     codename: xenial
+- name: TLP Power Management | Add Proposed Repository For acpi-call Hotfixes
+  tags: [x1yoga,system,tlp]
+  apt_repository:
+    repo: 'deb http://archive.ubuntu.com/ubuntu/ xenial-proposed restricted main multiverse universe'
+    filename: official-package-repositories
+    state: present
 - name: TLP Power Management | Install Packages
-  tags: [x1yoga,system]
+  tags: [x1yoga,system,tlp]
   package:
     name: "{{ item }}"
     state: latest
@@ -14,3 +20,10 @@
     - acpi-call
     - tlp
     - tlp-rdw
+- name: TLP Power Management | Remove Proposed Repository
+  tags: [x1yoga,system,tlp]
+  apt_repository:
+    repo: 'deb http://archive.ubuntu.com/ubuntu/ xenial-proposed restricted main multiverse universe'
+    filename: official-package-repositories
+    state: absent
+    update_cache: yes