fix: removal of [smp_]read_barrier_depends (v5.9)

See upstream commits:

  commit 76ebbe78f7390aee075a7f3768af197ded1bdfbb
  Author: Will Deacon <will@kernel.org>
  Date:   Tue Oct 24 11:22:47 2017 +0100

    locking/barriers: Add implicit smp_read_barrier_depends() to READ_ONCE()

    In preparation for the removal of lockless_dereference(), which is the
    same as READ_ONCE() on all architectures other than Alpha, add an
    implicit smp_read_barrier_depends() to READ_ONCE() so that it can be
    used to head dependency chains on all architectures.

  commit 76ebbe78f7390aee075a7f3768af197ded1bdfbb
  Author: Will Deacon <will.deacon@arm.com>
  Date:   Tue Oct 24 11:22:47 2017 +0100

    locking/barriers: Add implicit smp_read_barrier_depends() to READ_ONCE()

    In preparation for the removal of lockless_dereference(), which is the
    same as READ_ONCE() on all architectures other than Alpha, add an
    implicit smp_read_barrier_depends() to READ_ONCE() so that it can be
    used to head dependency chains on all architectures.

Change-Id: Ife8880bd9378dca2972da8838f40fc35ccdfaaac
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>