tidy-up: miscellaneous

- apply more clang-format.
- lib/version: use `CURL_ARRAYSIZE()`.
- INSTALL-CMAKE.md: sync-up an option description with others.
- examples: delete unused main args.
- examples/ftpgetinfo: document `_CRT_SECURE_NO_WARNINGS` symbol.
- delete remaining stray duplicate lines.
- acinclude.m4: drop an unnecessary x-hack.
- vtls/mbedtls: join a URL split into two lines.
- src/tool_cb_see: add parentheses around macro expressions.
- src/tool_operate: move literals to the right side of comparisons.
- libtests: sync up fopen/fstat error messages between tests.
- curl_setup.h: replace `if ! defined __LP64` with `ifndef __LP64`.
  I assume it makes no difference on Tandem systems, as the latter form
  is already used in `include/curl/system.h`.

Closes #20018

lib/tftp.c

@@ -143,7 +143,6 @@ struct tftp_conn {
   BIT(remote_pinned);
 };
 
-
 /* Forward declarations */
 static CURLcode tftp_rx(struct tftp_conn *state, tftp_event_t event);
 static CURLcode tftp_tx(struct tftp_conn *state, tftp_event_t event);
@@ -162,7 +161,6 @@ static CURLcode tftp_translate_code(tftp_error_t error);
 /*
  * TFTP protocol handler.
  */
-
 const struct Curl_handler Curl_handler_tftp = {
   "tftp",                               /* scheme */
   tftp_setup_connection,                /* setup_connection */