media: venus: hfi: return an error if session_init is already called

This makes hfi_session_init to return an error when it is
already called without a call to hfi_session_deinit.
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

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

@@ -198,6 +198,9 @@ int hfi_session_init(struct venus_inst *inst, u32 pixfmt)
 	const struct hfi_ops *ops = core->ops;
 	int ret;
 
+	if (inst->state != INST_UNINIT)
+		return -EINVAL;
+
 	inst->hfi_codec = to_codec_type(pixfmt);
 	reinit_completion(&inst->done);