format embedded struct declaration for check-format.pl

format embedded struct declaration for check-format.pl

so that subsequent commits to e_chacha20_poly1305.c doesn't trigger
warnings about handling '{' later in this file in related code.

i.e.

crypto/evp/e_chacha20_poly1305.c:610:indent = 0 != 4 for stmt/decl:static const EVP_CIPHER chacha20_poly1305 = {
crypto/evp/e_chacha20_poly1305.c:611:indent = 4 != 45 for hanging '{' or 8 for lines after '{':    NID_chacha20_poly1305,

Reviewed-by: Norbert Pocs <norbertp@openssl.org>
Reviewed-by: Tom Cosgrove <tom.cosgrove@arm.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/28588)