Copter: add EKF to Ch7/Ch8 Opt parameter description
HAL_PX4: read from FRAM in 128 byte chunks

this fixes FRAM read on Roberts Pixhawk. We don't know why yet.
Copter: update release notes for AC3.1.4-rc1
Revert "HAL_PX4: read from FRAM in 128 byte chunks"

This reverts commit a92366c4552851719cbdd0e5a92789f99f8bda6d.

This commit may be associated with FRAM corruption on Pixhawk. Revert
until we understand why
HAL_PX4: read from FRAM in 128 byte chunks (2nd try)

this time without the amazingly silly bug