Forgotten change of add() call in Configure

Reviewed-by: Matt Caswell <matt@openssl.org>

Configure

diff --git a/Configure b/Configure
index ad20bf6..06e1967 100755
--- a/Configure
+++ b/Configure
@@ -2081,7 +2081,7 @@
     #   value.
     # - Otherwise, this target's value is assumed to be a string that
     #   will simply override the inherited list of values.
-    my $default_combiner = add(" ");
+    my $default_combiner = add();
 
     my %all_keys =
 	map { $_ => 1 } (keys %combined_inheritance,