msm: kgsl: Don't map DDR as strongly ordered

Don't map DDR memory as strongly ordered because it makes the memory
controller sad. All we really care about is the cache characteristics
and write-combine is the same as far as those are concerned.

Change-Id: Ic0dedbad30785c8d7c24ad3249413139593029f0
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>