Fix Windows build.
(cherry picked from commit 5f4c5a902b0508eab235adecb34b236cdc0048a5)

util/mk1mf.pl

diff --git a/util/mk1mf.pl b/util/mk1mf.pl
index 3da139d..b05c4ae 100755
--- a/util/mk1mf.pl
+++ b/util/mk1mf.pl
@@ -455,10 +455,13 @@
 	}
 close(IN);
 
-# Remove opensslconf.h so it doesn't get updated if we configure a
-# different branch.
-$exheader =~ s/[^ ]+\/opensslconf.h//;
-$header =~ s/[^ ]+\/opensslconf.h//;
+if ($orig_platform eq 'copy')
+	{
+	# Remove opensslconf.h so it doesn't get updated if we configure a
+	# different branch.
+	$exheader =~ s/[^ ]+\/opensslconf.h//;
+	$header =~ s/[^ ]+\/opensslconf.h//;
+	}
 
 if ($fips)
 	{