disp: msm: sde: create a dummy smmu device for scm transactions

Since drm smmu device is configured to support only 32 bit addressing,
but IOMMU expects 64 bit addressing configured device. This change
creates a dummy device with 64 bit mask for addressing to map and unmap the
shared memory for any scm call.

Change-Id: If4de87e3402e5ad914563961967f2390adda5cd5
Signed-off-by: Narendra Muppalla <NarendraM@codeaurora.org>