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/mprintf.c

@@ -39,11 +39,11 @@ const unsigned char Curl_ldigits[] = "0123456789abcdef";
 /* Upper-case digits. */
 const unsigned char Curl_udigits[] = "0123456789ABCDEF";
 
-#define OUTCHAR(x)                                       \
-  do {                                                   \
-    if(stream((unsigned char)(x), userp))                \
-      return TRUE;                                       \
-    (*donep)++;                                          \
+#define OUTCHAR(x)                        \
+  do {                                    \
+    if(stream((unsigned char)(x), userp)) \
+      return TRUE;                        \
+    (*donep)++;                           \
   } while(0)
 
 /* Data type to read from the arglist */