tidy-up: miscellaneous

- examples: sync debug output printf masks.
- INSTALL-CMAKE.md: tidy up section for some options.
- curl_sha512_256: delete comment suggesting an optimization.
- vtls/keylog: scope a variable.
- vtls/openssl: make a source code URL a permalink.
- vtls/schannel: drop redundant parentheses.
- test1119.pl: robustify `$1` -> `$s`.
- sync arg names in comments to match the code.
- tidy up and minor fixes to comments.
- fix formatting/indenting/comment/newline/include nits.
- move `UNITTEST` protos next to definitions, sync their argument names.
- make variables static.
- add parentheses to Perl `open()` calls.
- drop unnecessary double quotes in Perl.
- clang-format.

Closes #21000

lib/http2.c

@@ -1734,8 +1734,8 @@ static CURLcode http2_handle_stream_close(struct Curl_cfilter *cf,
         break;
       curlx_dyn_reset(&dbuf);
       result = curlx_dyn_addf(&dbuf, "%.*s: %.*s\x0d\x0a",
-                            (int)e->namelen, e->name,
-                            (int)e->valuelen, e->value);
+                              (int)e->namelen, e->name,
+                              (int)e->valuelen, e->value);
       if(result)
         break;
       Curl_debug(data, CURLINFO_HEADER_IN, curlx_dyn_ptr(&dbuf),