tidy-up: miscellaneous

- vms/curlmsg_vms.h: delete unused/commented code.
- vtls/schannel_verify: sort includes.
- typecheck-gcc.h: fix indent and alignment.
- lib/config-win32.h: drop idle `#undef`.
- spacecheck: check for stray empty lines before after curly braces.
- make literals more readable: 1048576 -> 1024 * 1024
- scope variables.
- use ISO date in a comment.
- drop redundant parentheses.
- drop empty comments.
- unfold lines.
- duplicate/stray spaces in comments.
- fix indent, whitespace, minor typos.

Closes #20690

lib/socks.c

@@ -1339,7 +1339,6 @@ static CURLcode socks_cf_adjust_pollset(struct Curl_cfilter *cf,
 static void socks_proxy_cf_close(struct Curl_cfilter *cf,
                                  struct Curl_easy *data)
 {
-
   DEBUGASSERT(cf->next);
   cf->connected = FALSE;
   socks_proxy_cf_free(cf);