egl+vulkan: always compile `surfaceless`, and auto-detect `display` & `drm`
surfaceless
has no dependencies and costs virtually nothing to build. There is no downside to enabling it unconditionally, so let's do just that.
/cc @dbaker @evelikov
surfaceless
has no dependencies and costs virtually nothing to build. There is no downside to enabling it unconditionally, so let's do just that.
/cc @dbaker @evelikov