msm: mdss: fix smmu buffer mapping in recovery mode

When booting up in recovery mode, mmap is called without iommu attach.
This would result in device panic as iommu fails when buffer mapping is
done without attaching the respective iommu domain. Fix the issue by
delaying the mapping to a later point, during the commit.

Change-Id: Idbe4f6ca5557774b5add56c064ea6b05a67d530f
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>