drm/amdgpu: correct the memcpy size for ip discovery firmware

Use fw->size instead of discovery_tmr_size for fallback path.
Signed-off-by: Le Ma <le.ma@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -229,7 +229,7 @@ static int amdgpu_discovery_read_binary_from_file(struct amdgpu_device *adev, ui
 		return r;
 	}
 
-	memcpy((u8 *)binary, (u8 *)fw->data, adev->mman.discovery_tmr_size);
+	memcpy((u8 *)binary, (u8 *)fw->data, fw->size);
 	release_firmware(fw);
 
 	return 0;