mhi: mhi_uci: pass max payload size to mhi during mhi registration

MHI host requires clients to provide maximum payload size
during active transfer so MHI host can pre-allocate bounce
buffers.

CRs-Fixed: 1110280
Change-Id: I5dd38fc49a98629f77cdb7879942b7b1993e43b8
Signed-off-by: Sujeev Dias <sdias@codeaurora.org>