disp: msm: remove stale ION references

After adapting dma buf api's these references and
paths are unusable. Clean it up.

Change-Id: Id6fa76945132e312e8bacf6e430633b0db9e48a3
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>

msm/sde/sde_kms.h

@@ -19,7 +19,6 @@
 #ifndef __SDE_KMS_H__
 #define __SDE_KMS_H__
 
-#include <linux/msm_ion.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_qos.h>