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/cf-h2-proxy.c

@@ -685,15 +685,16 @@ static int proxy_h2_on_stream_close(nghttp2_session *session,
   return 0;
 }
 
-static CURLcode proxy_h2_submit(int32_t *pstream_id,
-                                struct Curl_cfilter *cf,
-                                struct Curl_easy *data,
-                                nghttp2_session *h2,
-                                struct httpreq *req,
-                                const nghttp2_priority_spec *pri_spec,
-                                void *stream_user_data,
-                               nghttp2_data_source_read_callback read_callback,
-                                void *read_ctx)
+static CURLcode proxy_h2_submit(
+  int32_t *pstream_id,
+  struct Curl_cfilter *cf,
+  struct Curl_easy *data,
+  nghttp2_session *h2,
+  struct httpreq *req,
+  const nghttp2_priority_spec *pri_spec,
+  void *stream_user_data,
+  nghttp2_data_source_read_callback read_callback,
+  void *read_ctx)
 {
   struct dynhds h2_headers;
   nghttp2_nv *nva = NULL;