Enable unstable API for early prototype development

configname: CONFIG_DRM_I915_UNSTABLE

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>drm/i915 Unstable Evolution
└─>Enable unstable API for early prototype development
In linux kernel since version 5.1 (release Date: 2019-05-05)  
Enable prototype uAPI under general discussion before they are
finalized. Such prototypes may be withdrawn or substantially
changed before release. They are only enabled here so that a wide
number of interested parties (userspace driver developers) can
verify that the uAPI meet their expectations. These uAPI should
never be used in production.

Recommended for driver developers _only_.

If in the slightest bit of doubt, say "N".

depends
CONFIG_BROKEN
CONFIG_DRM_I915
CONFIG_EXPERT
CONFIG_HAS_IOMEM
CONFIG_STAGING
NOT CONFIG_COMPILE_TEST