Enable amdgpu support for CIK parts

configname: CONFIG_DRM_AMDGPU_CIK

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>Enable amdgpu support for CIK parts
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Choose this option if you want to enable support for CIK (Sea
Islands) asics.

CIK is already supported in radeon. Support for CIK in amdgpu
will be disabled by default and is still provided by radeon.
Use module options to override this:

radeon.cik_support=0 amdgpu.cik_support=1