drm/amdgpu: Add asic func interface to init doorbell index

This is preparation to move doorbell index initialization
to amdgpu_asic_funcs
Signed-off-by: Oak Zeng <ozeng@amd.com>
Proposed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -654,6 +654,8 @@ struct amdgpu_asic_funcs {
 			       struct amdgpu_ring *ring);
 	/* check if the asic needs a full reset of if soft reset will work */
 	bool (*need_full_reset)(struct amdgpu_device *adev);
+	/* initialize doorbell layout for specific asic*/
+	void (*init_doorbell_index)(struct amdgpu_device *adev);
 };
 
 /*
@@ -1209,6 +1211,7 @@ int emu_soc_asic_init(struct amdgpu_device *adev);
 #define amdgpu_asic_flush_hdp(adev, r) (adev)->asic_funcs->flush_hdp((adev), (r))
 #define amdgpu_asic_invalidate_hdp(adev, r) (adev)->asic_funcs->invalidate_hdp((adev), (r))
 #define amdgpu_asic_need_full_reset(adev) (adev)->asic_funcs->need_full_reset((adev))
+#define amdgpu_asic_init_doorbell_index(adev) (adev)->asic_funcs->init_doorbell_index((adev))
 
 /* Common functions */
 bool amdgpu_device_should_recover_gpu(struct amdgpu_device *adev);