drm/amd/powerplay: remove smu mutex lock in smu_hw_init

the smu mutex lock is unnecessary in smu hw init.
Signed-off-by: Kevin Wang <kevin1.wang@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/powerplay/amdgpu_smu.c

@@ -981,8 +981,6 @@ static int smu_hw_init(void *handle)
 		}
 	}
 
-	mutex_lock(&smu->mutex);
-
 	ret = smu_feature_init_dpm(smu);
 	if (ret)
 		goto failed;
@@ -1011,8 +1009,6 @@ static int smu_hw_init(void *handle)
 	if (ret)
 		goto failed;
 
-	mutex_unlock(&smu->mutex);
-
 	if (!smu->pm_enabled)
 		adev->pm.dpm_enabled = false;
 	else