Improved CMAKE return value checking and ensured that fresh checkouts initialize the GIT submodules correctly

This is a workaround for the fact that the used information is not
shared between the ADSP and the Linux side on the Snapdragon. By
flagging all params used, we can at least receive them on QGC.

- experimented with reading rc data from uart but this fails
- mixer loading works

serial data on the snapdragon ESC connector (J13)

This should fix includes, as well as the gyro scaling.

The locking seems to be broken, therefore refrain from using it.

switch the modules implementing the block structure to px4_poll such that in posix_sitl simulation the poll works as expected, blocks the module and doesn't overload the CPU

improved position based flow correction for lpe

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