ARM: dts: msm: Add address-cells and size-cells for CNSS node

Add address-cells and size-cells for CNSS MHI node, which resolves
the warning of "reg property in /soc/qcom,cnss-qca6390@a0000000/mhi_chan@0
has invalid length (4 bytes) (#address-cells == 2, #size-cells == 1)"

Change-Id: I494b846af5c5195a105e903f2c23b1c5a4504fc4
Signed-off-by: Yuanyuan Liu <yuanliu@codeaurora.org>