Unable to run asm code on OpenBSD (amd64)

Unable to run asm code on OpenBSD (amd64)

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)