udf: Replace HTTP links with HTTPS ones

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Link: https://lore.kernel.org/r/20200713200738.37800-1-grandmaster@al2klimov.de
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Jan Kara <jack@suse.cz>

Documentation/filesystems/udf.rst

@@ -72,4 +72,4 @@ For the latest version and toolset see:
 
 Documentation on UDF and ECMA 167 is available FREE from:
 	- http://www.osta.org/
-	- http://www.ecma-international.org/
+	- https://www.ecma-international.org/