msm: mhi_dev: Fix race in MHI control state update

MHI control state can be updated to CONNECTED via the IPA
callback before MHI sets it to CONFIGURED. Check if it
is already updated in the callback to CONNECTED before setting it
to CONFIGURED.

Change-Id: Ia8506d2d1a700a1e122137f9fffe4ba16fb852c2
Signed-off-by: Siva Kumar Akkireddi <sivaa@codeaurora.org>