MHI supports downloading the device firmware over BHI/BHIe (Boot Host
Interface) protocol. Hence, this commit adds necessary helpers, which
will be called during device power up stage.

This is based on the patch submitted by Sujeev Dias:
https://lkml.org/lkml/2018/7/9/989Signed-off-by: NSujeev Dias <sdias@codeaurora.org>
Signed-off-by: NSiddartha Mohanadoss <smohanad@codeaurora.org>
[mani: splitted the data transfer patch and cleaned up for upstream]
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: NJeffrey Hugo <jhugo@codeaurora.org>
Tested-by: NJeffrey Hugo <jhugo@codeaurora.org>
Link: https://lore.kernel.org/r/20200220095854.4804-9-manivannan.sadhasivam@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>