Luoshuang's GPULightmass

[Jimbohalo10]

@3darchstuffs.com ,
The original Epic Lightmass for 5.4 will probably work,
The 5.4 version is available at

LGPU 5.4 BINARY announcement

UnrealEngine-5/README.md at Luoshuangs-GPULightmass-5.4-preview · jimshalo10/UnrealEngine-5 (github.com)