Replace HTTP links with HTTPS ones: vsprintf

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 both the HTTP and HTTPS versions
          return 200 OK and serve the same content:
            Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200702200536.13389-1-grandmaster@al2klimov.de

Author: Al2Klimov

Documentation/core-api/printk-formats.rst

@@ -317,7 +317,7 @@ colon-separators. Leading zeros are always used.
 
 The additional ``c`` specifier can be used with the ``I`` specifier to
 print a compressed IPv6 address as described by
-http://tools.ietf.org/html/rfc5952
+https://tools.ietf.org/html/rfc5952
 
 Passed by reference.
 
@@ -341,7 +341,7 @@ The additional ``p``, ``f``, and ``s`` specifiers are used to specify port
 flowinfo a ``/`` and scope a ``%``, each followed by the actual value.
 
 In case of an IPv6 address the compressed IPv6 address as described by
-http://tools.ietf.org/html/rfc5952 is being used if the additional
+https://tools.ietf.org/html/rfc5952 is being used if the additional
 specifier ``c`` is given. The IPv6 address is surrounded by ``[``, ``]`` in
 case of additional specifiers ``p``, ``f`` or ``s`` as suggested by
 https://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-07

lib/vsprintf.c

@@ -2134,7 +2134,7 @@ char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode,
  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
  * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
  * - 'I[6S]c' for IPv6 addresses printed as specified by
- *       http://tools.ietf.org/html/rfc5952
+ *       https://tools.ietf.org/html/rfc5952
  * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
  *                of the following flags (see string_escape_mem() for the
  *                details):