lib: fix some format specifiers

- Use CURL_FORMAT_CURL_OFF_T where %zd was erroneously used for some
  curl_off_t variables.

- Use %zu where %zd was erroneously used for some size_t variables.

Prior to this change some of the Windows CI tests were failing because
in Windows 32-bit targets have a 32-bit size_t and a 64-bit curl_off_t.
When %zd was used for some curl_off_t variables then only the lower
32-bits was read and the upper 32-bits would be read for part or all of
the next specifier.

Fixes https://github.com/curl/curl/issues/11327
Closes https://github.com/curl/curl/pull/11321

lib/vssh/wolfssh.c

@@ -277,7 +277,7 @@ static ssize_t wsftp_send(struct Curl_easy *data, int sockindex,
     return -1;
   }
   DEBUGASSERT(rc == (int)len);
-  infof(data, "sent %zd bytes SFTP from offset %zd",
+  infof(data, "sent %zu bytes SFTP from offset %" CURL_FORMAT_CURL_OFF_T,
         len, sshc->offset);
   sshc->offset += len;
   return (ssize_t)rc;