Configure: pass -no-integrated-as.

Occasionally you have to pass -no-integrated-as to clang, but we
consider any -no-option as no-option. Don't touch -no-integrated-as.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5613)
diff --git a/Configure b/Configure
index 8efd8bf..9b89f60 100755
--- a/Configure
+++ b/Configure
@@ -638,7 +638,9 @@
 		{
 		s/^([^=]*)/lc($1)/e;
 		}
-	s /^-no-/no-/; # some people just can't read the instructions
+
+	# some people just can't read the instructions, clang people have to...
+	s/^-no-(?!integrated-as)/no-/;
 
 	# rewrite some options in "enable-..." form
 	s /^-?-?shared$/enable-shared/;