Для чего нужен graw.so/dll?

This is an API for exercising gallium functionality in a platform-neutral fashion. Whatever platform integration is necessary to implement this interface is orchestrated by the individual target building this entity. For instance, the graw-xlib target includes code to implement these interfaces on top of the X window system. Programs using this interface may additionally benefit from some of the utilities currently in the libgallium.a library, especially those for parsing text representations of TGSI shaders.

Это бэкдор для АНБ. Не удаляй, а то ещё руткитов накидают.