msm: kgsl: Set the I/O coherent feature earlier

Some of the KGSL core code needs to make a decision about I/O coherency
so set the MMU property earlier to prevent an unneeded warning.

Change-Id: Ic0dedbadf9e4665b3e20460cb6f2ca81d74847e0
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>