perf/x86/rapl: Move RAPL support to common x86 code

To prepare for support of both Intel and AMD RAPL.

As per the AMD PPR, Fam17h support Package RAPL counters to monitor power usage.
The RAPL counter operates as with Intel RAPL, and as such it is beneficial
to share the code.

No change in functionality.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-2-eranian@google.com