Build fixes for qurt after rebase on PX4 master

Removed the re-definitions of the usage method in the posix/main.cpp file.
Added qurt_external_hook interface to call externally linked module.
Fixed code format to comply with PX4 style.
Added usage information to main app and handled cases for unknown arguments.
Fixed the orb_priority interface to use int32_t instead of int.
Fixes to get hil working with led changes.
Added the config_eagle_adsp.mk file and update the make files to to use new
include/lib paths

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