platforms: reorg after rebase on new board config

The new board config changed everything, so I needed to move the
lockstep_scheduler repo.

boards/px4/sitl/default.cmake

@@ -97,3 +97,6 @@ if(REPLAY_FILE)
 	message("Building with uorb publisher rules support")
 	add_definitions(-DORB_USE_PUBLISHER_RULES)
 endif()
+
+add_definitions(-D__PX4_POSIX_SITL)
+set(LOCKSTEP_SCHEDULER_NEEDED yes)

platforms/posix/src/CMakeLists.txt

@@ -31,5 +31,9 @@
 #
 ############################################################################
 
+if (LOCKSTEP_SCHEDULER_NEEDED)
+	add_subdirectory(lockstep_scheduler)
+endif()
+
 add_subdirectory(px4_daemon)
 add_subdirectory(px4_layer)

platforms/posix/src/px4_layer/CMakeLists.txt

@@ -58,7 +58,7 @@ target_link_libraries(px4_layer PRIVATE px4_daemon)
 
 if(LOCKSTEP_SCHEDULER_NEEDED)
 	target_link_libraries(px4_layer PRIVATE lockstep_scheduler)
-	include_directories(${PX4_SOURCE_DIR}/src/platforms/posix/lockstep_scheduler/include)
+	include_directories(${PX4_SOURCE_DIR}/platforms/posix/src/lockstep_scheduler/include)
 endif()