libressl: --disable-asm on x86_64

[aeiouaeiouaeiouaeiouaeiouaeiou]

The ​last commit actually worsened the build. Compiling assembly code now requires a newer version of clang, which causes unwanted dependency recursion on a clean system (clang-16 -> python311 -> openssl).

It might be worth disabling compilation of this code, but it's hard for me to check, since debugging is complicated by the fact that many ports use openssl and my laptop keeps trying to download it.