Make the peak refresh rate with rounding

To ensure accurate comparison of peak refresh rates, it is essential
to consider the peak refresh rate after rounding. This eliminates the
risk of unexpected triggers that could activate the Smooth Display
settings UI.

Bug: 312121651
Test: check the settings with Smooth Display
Change-Id: I4cd68efbcf4fdb9d4664c96332901661a23f4f09