Install gen-sshd-host-keys package

This will allow us to drop the host key generation from the
image generation scripts.

debian/changelog

-librem5-base (1) UNRELEASED; urgency=medium
+librem5-base (1) unstable; urgency=medium
 
-  * Add meta packages
+  * Install gen-sshd-host-keys package.
+    This will allow us to drop the host key generation from the
+    image generation scripts.
 
- -- Guido Günther <agx@sigxcpu.org>  Thu, 13 Sep 2018 12:44:26 +0200
+ -- Guido Günther <agx@sigxcpu.org>  Wed, 19 Sep 2018 11:23:47 +0200
 
 librem5-themes (0) unstable; urgency=medium
 

debian/control

@@ -24,6 +24,7 @@ Depends:
  locales,
  lvm2,
  modemmanager,
+ gen-sshd-host-keys,
  usb-modeswitch,
  usbutils,
  librem5-base-defaults (>= ${source:Version}),