platform: msm: qcom-geni-se: Configure context bank device node

Configure the context bank device node default
value to geni device node to use geni device node
for dma memory allocation in the case of context bank
node is disabled. Iommu map and attach is not done if
iommu-dma bypass is set.

Change-Id: I1a1c17320de6b768b58bc73ee075659f3e90058d
Signed-off-by: Dilip Kota <dkota@codeaurora.org>