Handle edge-cases in gencerts

Make sure that we exit with success if the files already exist and
that we exit with failure and a message if only one or the other
is present.

httpd-ssl-gencerts

@@ -4,11 +4,24 @@ set -e
 
 FQDN=`hostname`
 
-if test -f /etc/pki/tls/certs/localhost.crt -o \
+if test -f /etc/pki/tls/certs/localhost.crt -a \
         -f /etc/pki/tls/private/localhost.key; then
+    exit 0
+fi
+
+if test -f /etc/pki/tls/certs/localhost.crt -a \
+        ! -f /etc/pki/tls/private/localhost.key; then
+    echo "Missing certificate key!"
     exit 1
 fi
 
+if test ! -f /etc/pki/tls/certs/localhost.crt -a \
+         -f /etc/pki/tls/private/localhost.key; then
+    echo "Missing certificate, but key is present!"
+    exit 1
+fi
+
+
 sscg -q                                                             \
      --cert-file           /etc/pki/tls/certs/localhost.crt         \
      --cert-key-file       /etc/pki/tls/private/localhost.key       \