Inconsistent `seg_t::angle` handling in software renderring

[elf-alchemist]

When running on software renderring mode, some ports will take the seg_t::angle property into account differently, while often harmless, this change can break levels with nodebuilder compiled seg-manipulation, this affects the official expansion Legacy Of Rust's MAP10 (E2M3: Dis Union)'s infinite lava horizon effect.

Horizon Test WAD: horizon.zip

Crispy -- Horizon Test WAD -- 🟢 effect looks as intended

Woof -- Legacy Of Rust -- 🟢 effect looks as intended

DoomRetro -- Legacy Of Rust -- 🟢 effect looks as intended

KEX -- Legacy Of Rust -- 🟢 effect looks as intended

DSDA -- Legacy Of Rust -- ❌ effect looks incorrect

Eternity -- Legacy Of Rust -- ❌ effect looks incorrect

Odamex -- Legacy Of Rust -- ❌ effect looks incorrect