perf/x86/intel/rapl: Clean up the printk output

perf/x86/intel/rapl: Clean up the printk output

The output is inconsistent. Use a proper pr_fmt prefix and split out the
advertisement into a seperate function.

Remove the WARN_ON() in the failure case. It's pointless as we already know
where it failed.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Harish Chegondi <[email protected]>
Cc: Jacob Pan <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>