Commander: start pulling arming related parts into separate folder

* PreFlightCheck: remove unused reportFailures flag
* Commander: pull all pre flight checks together on the PreFlightCheck class
* PreFlightCheck: separate checks into their own files

src/modules/commander/commander_tests/CMakeLists.txt

@@ -37,6 +37,5 @@ px4_add_module(
 		commander_tests.cpp
 		state_machine_helper_test.cpp
 		../state_machine_helper.cpp
-		../PreflightCheck.cpp
 	DEPENDS
 	)

src/modules/commander/commander_tests/state_machine_helper_test.cpp

@@ -42,6 +42,7 @@
 
 #include "../state_machine_helper.h"
 #include <unit_test.h>
+#include "../Arming/PreFlightCheck/PreFlightCheck.hpp"
 
 class StateMachineHelperTest : public UnitTest
 {
@@ -304,7 +305,7 @@ bool StateMachineHelperTest::armingStateTransitionTest()
 					     true /* enable pre-arm checks */,
 					     nullptr /* no mavlink_log_pub */,
 					     &status_flags,
-					     (check_gps ? ARM_REQ_GPS_BIT : 0),
+					     (check_gps ? PreFlightCheck::ARM_REQ_GPS_BIT : 0),
 					     2e6 /* 2 seconds after boot, everything should be checked */
 								    );