-can't sync after deinit

Instead of calculating time offsets between samples, it is easier just
to assume a constant sampling time. Then all samples can be integrated,
and published every forth time the FIFO buffer has been emptied.

The sampling in the sensor happens at 8kHz, the driver empties the
buffer at 1kHz, and publishes (and resets the integration) at 250 Hz.

This adds a second put method to the integrator class. This allows to
integrate with known intervals between samples, rather than based on
timestamps. This makes integrating the samples coming out of the MPU9250
FIFO buffer easier.

if fuseOptFlowData == false, then K_LOS was not initialized, but it was
accessed in the next fuse block to update states variable.

This fixes a memory leak

in order to avoid memory management

muorb: call `initialize()` before `get_instance()`

* Use DriverFramework as a PX4 module

Targets wanting to use DriverFramework must add

   lib/DriverFramework/framework

to their config file.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

* Removed spurious code

No need to add if check before for loop

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

* Added DriverFramework to NuttX configs

Added lib/DriverFramework/firmware to nuttx configs

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

* Updated src/lib/DriverFramework

* Removed DF_TARGET and __DF_${OS} defines

These are now handled inside DriverFramework

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

* Updated DriverFramework

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

* Restored __DF_${OS}

The include files in DriverFramwork need to know the target OS.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>