Update setup-sshd.sh

Signed-off-by: Zoey <zoey@z0ey.de>

setup-sshd.sh

@@ -1,5 +1,12 @@
 #!/bin/sh
 
+if ! echo "$SSH_PUBKEY" | grep -q "^ssh-.*$"; then
+    echo "SSH_PUBKEY needs to start with ssh-."
+    sleep inf
+fi
+
+ssh-keygen -A
+mkdir -vp /tmp/.ssh
 echo "$SSH_PUBKEY" | tee -a /tmp/.ssh/authorized_keys
 
 exec /usr/sbin/sshd -De