rpmsg: glink: Fix memory leak in qcom_glink_alloc_intent()

We need to free "intent" and "intent->data" on a couple error paths.

Fixes: 933b45da ("rpmsg: glink: Add support for TX intents")
Acked-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>