[openssl/openssl] 24a322: dtls: code cleanup and refactorization

[FdaSilvaYY]

  Branch: refs/heads/master
  Home:   https://github.com/openssl/openssl
  Commit: 24a322544373f7acda05e19f64a6c3120d459d5b
      https://github.com/openssl/openssl/commit/24a322544373f7acda05e19f64a6c3120d459d5b
  Author: FdaSilvaYY <fdasilvayy at gmail.com>
  Date:   2023-04-24 (Mon, 24 Apr 2023)

  Changed paths:
    M ssl/d1_lib.c
    M ssl/ssl_local.h

  Log Message:
  -----------
  dtls: code cleanup and refactorization

- factorize BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT calls.
- simplify a return type
- style nits

Reviewed-by: Todd Short <todd.short at me.com>
Reviewed-by: Tomas Mraz <tomas at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/20602)