x86, intel, power: Correct the MSR_IA32_ENERGY_PERF_BIAS message

Fix the printk_once() so that it actually prints (didn't print before
due to a stray comma.)

[ hpa: changed to an incremental patch and adjusted the description
  accordingly. ]

Signed-off-by: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107151732480.18606@x980


Cc: <table@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>