tools/power/x86/intel-speed-select: Display error for invalid priority type

When priority type for core-power enable command is anything more than 1
display error before change to 1, which is ordered priority.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>