staging/android: move trace/sync.h to sync_trace.h

The common behaviour for trace headers is to have them in the same folder
they are used, instead of creating a special trace/ directory.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>