In order to get asm code running on OpenBSD we must place
all constants into .rodata sections.
davidben@ also pointed out we need to adjust `x86_64-xlate.pl` perlasm
script to adjust read-olny sections for various flavors (OSes). Those
changes were cherry-picked from boringssl.
closes#23312
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23997)