staging/android: add TODO to de-stage android sync framework

- remove CONFIG_SW_SYNC_USER, it is used only for testing/debugging and
should not be upstreamed.
- port CONFIG_SW_SYNC_USER tests interfaces to use debugfs somehow
- port libsync tests to kselftest
- clean up and ABI check for security issues
- move the sync framework to drivers/base/dma-buf

Cc: Arve Hjønnevåg <[e-mail]>
Cc: Riley Andrews <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Rob Clark <[e-mail]>
Cc: Greg Hackmann <[e-mail]>
Cc: John Harrison <[e-mail]>
Signed-off-by: Gustavo Padovan <[e-mail]>
Acked-by: Daniel Vetter <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/android/TODO

···
    exposes existing cma regions and doesn't reserve unecessarily memory when
    booting a system which doesn't use ion.
 
+sync framework:
+ - remove CONFIG_SW_SYNC_USER, it is used only for testing/debugging and
+ should not be upstreamed.
+ - port CONFIG_SW_SYNC_USER tests interfaces to use debugfs somehow
+ - port libsync tests to kselftest
+ - clean up and ABI check for security issues
+ - move it to drivers/base/dma-buf
+
 Please send patches to Greg Kroah-Hartman <[e-mail]> and Cc:
 Arve Hjønnevåg <[e-mail]> and Riley Andrews <[e-mail]>