drm/amd/amdgpu/amdgpu_ras: Remove unused function 'amdgpu_ras_error_cure'

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

 drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:908:5: warning: no previous prototype for ‘amdgpu_ras_error_cure’ [-Wmissing-prototypes]

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>

drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c

@@ -905,13 +905,6 @@ int amdgpu_ras_error_inject(struct amdgpu_device *adev,
 	return ret;
 }
 
-int amdgpu_ras_error_cure(struct amdgpu_device *adev,
-		struct ras_cure_if *info)
-{
-	/* psp fw has no cure interface for now. */
-	return 0;
-}
-
 /* get the total error counts on all IPs */
 unsigned long amdgpu_ras_query_error_count(struct amdgpu_device *adev,
 		bool is_ce)