media: venus: hfi: avoid null dereference in deinit

If venus_probe fails at pm_runtime_put_sync the error handling first
calls hfi_destroy and afterwards hfi_core_deinit. As hfi_destroy sets
core->ops to NULL, hfi_core_deinit cannot call the core_deinit function
anymore.

Avoid this null pointer derefence by skipping the call when necessary.
Signed-off-by: NLuca Weiss <luca.weiss@fairphone.com>
Signed-off-by: NStanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/qcom/venus/hfi.c

@@ -104,6 +104,9 @@ int hfi_core_deinit(struct venus_core *core, bool blocking)
 		mutex_lock(&core->lock);
 	}
 
+	if (!core->ops)
+		goto unlock;
+
 	ret = core->ops->core_deinit(core);
 
 	if (!ret)