initial minimal PX4_ROS2 platform and px4_ros2_default build (#20689)

- new ROS2 platform in PX4 intended for creating configs that build and run entirely in ROS2
 - PX4_CONFIG defaults to px4_ros2_default if no config specified and in a colcon workspace with ROS_VERSION=2
 - currently doesn't do much other than allow you to build px4 msgs interface package

src/drivers/bootloaders/CMakeLists.txt

@@ -39,7 +39,7 @@ add_dependencies(drivers_bootloaders prebuild_targets)
 
 include_directories(include)
 target_include_directories(drivers_bootloaders INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
-target_link_libraries(drivers_bootloaders PRIVATE systemlib)
+target_link_libraries(drivers_bootloaders PRIVATE crc)
 
 # generate bootloader_app_shared_t
 if(NOT "${PX4_BOARD_LABEL}" MATCHES  "canbootloader")

src/drivers/bootloaders/boot_alt_app_shared.c

@@ -45,7 +45,7 @@
 
 #include "boot_alt_app_shared.h"
 
-#include <lib/systemlib/crc.h>
+#include <lib/crc/crc.h>
 
 /****************************************************************************
  * Name: bootloader_alt_app_shared_read

src/drivers/bootloaders/boot_app_shared.c

@@ -46,7 +46,7 @@
 #include "arm_internal.h"
 #include "boot_app_shared.h"
 
-#include <lib/systemlib/crc.h>
+#include <lib/crc/crc.h>
 
 #define BOOTLOADER_COMMON_APP_SIGNATURE         0xB0A04150u
 #define BOOTLOADER_COMMON_BOOTLOADER_SIGNATURE  0xB0A0424Cu