msm: mhi_dev: add MHI device driver snapshot

Modem host interface (MHI) device driver is
used to communicate between host and device
over PCIe.

This snapshot is taken as of msm-4.9
'commit <16158207fb4c> ("Merge "f_qc_rndis: Call
rndis_ipa_init() from rndis_qc_bind()")'.

Update handling of error conditions.

Change-Id: I5ffdaedd7f384bedb89eecd7773289b9bc399c93
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>