Replace __unused in linux/sysctl.h with __linux_unused

To avoid conflict with "#define __unused" in sys/cdefs.h

See
  https://android-review.googlesource.com/#/c/43479
  https://android-review.googlesource.com/#/c/43565

Change-Id: I6b8155570f4398b3ee8845d75bd231bca7f1d86f
2 files changed