perf c2c: Change header from "LLC Load Hitm" to "Load Hitm"

The metrics "LLC Load Hitm" contains two items: one is "local Hitm" and
another is "remote Hitm".

"local Hitm" means: L3 HIT and was serviced by another processor core
with a cross core snoop where modified copies were found; it's no doubt
that "local Hitm" belongs to LLC access.

But for "remote Hitm", based on the code in util/mem-events, it's the
event for remote cache HIT and was serviced by another processor core
with modified copies.  Thus the remote Hitm is a remote cache's hit and
actually it's LLC load miss.

Now the display format gives users the impression that "local Hitm" and
"remote Hitm" both belong to the LLC load, but this is not the fact as
described.

This patch changes the header from "LLC Load Hitm" to "Load Hitm", this
can avoid the give the wrong impression that all Hitm belong to LLC.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Joe Mario <jmario@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201014050921.5591-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>