perf/x86: Enable DRAM RAPL support on Intel Haswell

It turns out all Haswell processors (including the Desktop
variant)  support RAPL DRAM readings in addition to package,
pp0, and pp1.

I've confirmed RAPL DRAM readings on my model 60 Haswell
desktop.

See the 4th-gen-core-family-desktop-vol-2-datasheet.pdf
available from the Intel website for confirmation.

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Stephane Eranian <eranian@gmail.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1404020045290.17889@vincent-weaver-1.um.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>