qdss_bridge: fix kfree issue

The "opened" state can be changed to ENABLE only if the
mhi_queue_inbound() call succeed in mhi_uci_open(). This ensures
that mhi_buf_tbl is initialized when the "opened" state is ENABLE.

Change-Id: I2749d15f3fc317cc6a874a14bc8a49bdc64a8a73
Signed-off-by: Yuanfang Zhang <zhangyuanfang@codeaurora.org>