staging: android: Remove ion device tree bindings from the TODO

Commit 23a4388 ("staging: android: ion: Remove file ion_chunk_heap.c")
and eadbf7a ("staging: android: ion: Remove file ion_carveout_heap.c")
removed the chunk and carveout heaps from ion but left behind the device
tree bindings for them in the TODO, this patch removes it.

Signed-off-by: Donald Yandt <donald.yandt@gmail.com>
Link: https://lore.kernel.org/r/20190818152023.891-1-donald.yandt@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/TODO

@@ -6,8 +6,6 @@ TODO:
 
 
 ion/
- - Add dt-bindings for remaining heaps (chunk and carveout heaps). This would
-   involve putting appropriate bindings in a memory node for Ion to find.
  - Split /dev/ion up into multiple nodes (e.g. /dev/ion/heap0)
  - Better test framework (integration with VGEM was suggested)