gpu: ion: Add compatibility with future changes

Several changes are pending to be pulled in which are
not compatible with our changes. Specifically, a new
field to the allocation ioctl is added and the ioctl
numbers for cache flushing need to be changed.
Add these changes now until full changes can be pulled
in the future.

Change-Id: I9540495e25c7b6c414a6e3719f66f2cd9f78c585
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Ajay Dudani <adudani@codeaurora.org>