gpu: ion: Add one empty line for readability

For readability.

Change-Id: I3f197e584f81b748c04d4eb7711bb4082492c441
Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Reviewed-on: http://git-master/r/75529
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Varun Wadekar <vwadekar@nvidia.com>