Document what's going on in asm/backoff.h with a large and descriptive
comment. Refer to it above the cpu_relax() definition in
asm/processor_64.h
Rename the pause patching section to have "3insn" in it's name like
the other patching sections do.
Based upon feedback from Sam Ravnborg.
Signed-off-by: David S. Miller <davem@davemloft.net>
187818cd6a