commit 2a41b6dc upstream.

commit 80f42084 removed the ARC bitops microoptimization but failed
to prune the comments to same effect

Fixes: 80f42084 ("ARC: Make ARC bitops "safer" (add anti-optimization)")
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>