recipes-images: add fragement to install sshkeys

Fixes: partly SYS#518

recipes-apps/images/image-sshkey.inc

@@ -0,0 +1,18 @@
+
+hostsshkeysfile = "${@d.getVar('SSH_KEYS_FILE', True) or ''}"
+
+ROOTFS_POSTPROCESS_COMMAND += "copy_ssh_keys;"
+
+copy_ssh_keys() {
+    if [ -n "${hostsshkeysfile}" ]; then
+        if [ -r "${hostsshkeysfile}" ]; then
+            echo "Installing sshkeys from ${hostsshkeysfile}"
+            mkdir -p ${IMAGE_ROOTFS}/home/root/.ssh/
+            cat ${hostsshkeysfile} >> ${IMAGE_ROOTFS}/home/root/.ssh/authorized_keys
+            chown root:root ${IMAGE_ROOTFS}/home/root/.ssh/authorized_keys
+            chmod 0600 ${IMAGE_ROOTFS}/home/root/.ssh/authorized_keys
+        else
+            echo "Could not install sshkeys from ${hostsshkeysfile}"
+        fi
+    fi
+}