drm/amd: Remove unused declarations

amdgpu_gart_table_vram_pin() and amdgpu_gart_table_vram_unpin() has
been removed since commit 575e55ee4fbc ("drm/amdgpu: recover gart table
at resume") remain the declarations untouched in the header files.

Besides, amdgpu_dm_display_resume() has also beed removed since
commit a80aa93de1a0 ("drm/amd/display: Unify dm resume sequence into a
single call"). So, let's remove this unused declarations.

Signed-off-by: Zhang Zekun <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 static inline void amdgpu_choose_low_power_state(struct amdgpu_device *adev) { }
 #endif
 
-#if defined(CONFIG_DRM_AMD_DC)
-int amdgpu_dm_display_resume(struct amdgpu_device *adev );
-#else
-static inline int amdgpu_dm_display_resume(struct amdgpu_device *adev) { return 0; }
-#endif
-
-
 void amdgpu_register_gpu_instance(struct amdgpu_device *adev);
 void amdgpu_unregister_gpu_instance(struct amdgpu_device *adev);
 

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

···
 void amdgpu_gart_table_ram_free(struct amdgpu_device *adev);
 int amdgpu_gart_table_vram_alloc(struct amdgpu_device *adev);
 void amdgpu_gart_table_vram_free(struct amdgpu_device *adev);
-int amdgpu_gart_table_vram_pin(struct amdgpu_device *adev);
-void amdgpu_gart_table_vram_unpin(struct amdgpu_device *adev);
 int amdgpu_gart_init(struct amdgpu_device *adev);
 void amdgpu_gart_dummy_page_fini(struct amdgpu_device *adev);
 void amdgpu_gart_unbind(struct amdgpu_device *adev, uint64_t offset,