mkinitramfs: use dropbear_install_hostkey() when available

initramfs/etc_mkinitramfs.d_40-ssh.sh.txt

@@ -3,7 +3,7 @@
 # This copyright note is auto-generated by ./scripts/Create-CopyPatch.
 #
 # Filename: target/idunn/initramfs/etc_mkinitramfs.d_40-ssh.sh.txt
-# Copyright (C) 2008 The OpenSDE Project
+# Copyright (C) 2008 - 2010 The OpenSDE Project
 #
 # More information can be found in the files COPYING and README.
 #
@@ -15,9 +15,13 @@
 
 . "$libdir/ssh.in"
 
+if ! type dropbear_install_hostkey > /dev/null 2>&1; then
+	dropbear_install_hostkey() { false; }
+fi
+
 # host keys
 for x in rsa dsa; do
-	openssh_install_hostkey "$x"
+	openssh_install_hostkey "$x" || dropbear_install_hostkey "$x"
 done
 
 # root authorized_keys