bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture

bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture

The bhie field in mhi_cntrl needs to be initialized to proper register
base in order to make mhi_rddm_prepare() to work. Otherwise,
mhi_rddm_prepare() will cause NULL pointer dereference.

Fixes: 6fdfdd27328c ("bus: mhi: core: Add support for downloading RDDM image during panic")
Reported-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200324061050.14845-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>