[openssl/openssl] 8712db: bn_nist: fix strict aliasing problem

[pauli]

  Branch: refs/heads/master
  Home:   https://github.openssl.org/openssl/openssl
  Commit: 8712db5e4e0c508de10e887aebf639384dc20710
      https://github.openssl.org/openssl/openssl/commit/8712db5e4e0c508de10e887aebf639384dc20710
  Author: Pauli <pauli at openssl.org>
  Date:   2022-05-10 (Tue, 10 May 2022)

  Changed paths:
    M crypto/bn/bn_nist.c

  Log Message:
  -----------
  bn_nist: fix strict aliasing problem

As of clang-14 the strict aliasing is causing code to magically disappear.
By explicitly inlining the code, the aliasing problem evaporates.

Fixes #18225

Reviewed-by: Tomas Mraz <tomas at openssl.org>
Reviewed-by: Tim Hudson <tjh at openssl.org>
Reviewed-by: Matt Caswell <matt at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/18258)