Improvements and bug fixes for external vision processing and filter initialisation

Sets zero values as a placeholder until mavlink can be updated.

Put struct definitions in enum order
Fix duplicate enum value
Add ekf2 replay message for external vision data

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

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

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

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

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

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

The FC_ADDON drivers are shared libraries that have PX4 wrappers.
The wrappers are built as modules which are static libraries and
cannot have shared library dependencies.

The shared libraries are required to resolve the symbols at runtime
and need to be linked with the libmainapp shared library.

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

Previous did not match the matlab simulation in: https://github.com/priseborough/InertialNav/blob/master/models/imu_error_modelling.m

The name uart_esc was initially taken by Qualcomm's UART ESC driver but
then got changed into the current mavlink ESC/RC helper. Since the
uart_esc is still around, we should prevent the names clashing.