Add clearFrameRate API in ndk

This API is same as using setFrameRate with 0 as frame-rate value. But
this causes confusion, as the remaining two arguments are ignored, when
frame-rate is 0.

Bug: 241096917
Test: android.graphics.cts.SetFrameRateTest#testClearFrameRate
Change-Id: I469e41cc1a15abf4c0b402caca12a9f6db4cdb71