tools/power/x86/intel-speed-select: Change display of "avx" to "avx2"

Make the avx level display consistent. Except for "turbo-ratio-limits-avx",
everywhere else it is avx2. So change "turbo-ratio-limits-avx"
to "turbo-ratio-limits-avx2".

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