drm/radeon: Add CP init for CIK (v7)

Sets up the GFX ring and loads ucode for GFX and Compute.

Todo:
- handle compute queue setup.

v2: add documentation
v3: integrate with latest reset changes
v4: additional init fixes
v5: scratch reg write back no longer supported on CIK
v6: properly set CP_RB0_BASE_HI
v7: rebase

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --cc drivers/gpu/drm/radeon/Makefile
Simple merge

diff --cc drivers/gpu/drm/radeon/cik.c
Simple merge

diff --cc drivers/gpu/drm/radeon/cik_blit_shaders.c
Simple merge

diff --cc drivers/gpu/drm/radeon/cik_blit_shaders.h
Simple merge

diff --cc drivers/gpu/drm/radeon/cikd.h
Simple merge

diff --cc drivers/gpu/drm/radeon/radeon_cs.c
Simple merge