Revert "Revert "Merge pull request #971 from metropt/update_gyro_rate_ff3""

This reverts commit 817a823da129aa00be66108fe5527d07fdbec9b9.
Initial sensor read after rate change
only set the sample rate on board config, clean-up
fix typo in function description and correct function parameter
Merge pull request #1100 from metropt/flyingf3_sensor_rate_fix

Flyingf3 sensor rate fix