Fixes the following W=1 kernel build warning(s):

 In file included from drivers/gpu/drm/amd/amdgpu/../display/dc/dce100/dce100_resource.c:54:
 drivers/gpu/drm/amd/amdgpu/../include/asic_reg/dce/dce_10_0_sh_mask.h:5084:45: warning: initialized field overwritten [-Woverride-init]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:155:28: note: in expansion of macro ‘GRPH_CONTROL__GRPH_NUM_BANKS__SHIFT’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:170:2: note: in expansion of macro ‘SFB’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:291:2: note: in expansion of macro ‘MI_GFX8_TILE_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce100/dce100_resource.c:537:3: note: in expansion of macro ‘MI_DCE8_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../include/asic_reg/dce/dce_10_0_sh_mask.h:5084:45: note: (near initialization for ‘mi_shifts.GRPH_NUM_BANKS’)
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:155:28: note: in expansion of macro ‘GRPH_CONTROL__GRPH_NUM_BANKS__SHIFT’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:170:2: note: in expansion of macro ‘SFB’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:291:2: note: in expansion of macro ‘MI_GFX8_TILE_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce100/dce100_resource.c:537:3: note: in expansion of macro ‘MI_DCE8_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../include/asic_reg/dce/dce_10_0_sh_mask.h:5083:43: warning: initialized field overwritten [-Woverride-init]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:155:28: note: in expansion of macro ‘GRPH_CONTROL__GRPH_NUM_BANKS_MASK’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:170:2: note: in expansion of macro ‘SFB’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:291:2: note: in expansion of macro ‘MI_GFX8_TILE_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce100/dce100_resource.c:542:3: note: in expansion of macro ‘MI_DCE8_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../include/asic_reg/dce/dce_10_0_sh_mask.h:5083:43: note: (near initialization for ‘mi_masks.GRPH_NUM_BANKS’)
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:155:28: note: in expansion of macro ‘GRPH_CONTROL__GRPH_NUM_BANKS_MASK’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:170:2: note: in expansion of macro ‘SFB’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dce_mem_input.h:291:2: note: in expansion of macro ‘MI_GFX8_TILE_MASK_SH_LIST’
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce100/dce100_resource.c:542:3: note: in expansion of macro ‘MI_DCE8_MASK_SH_LIST’

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>