Fixed led and reboot linker challenges in C++ environments

src/drivers/blinkm/blinkm.cpp

@@ -92,7 +92,10 @@
 
 #include <nuttx/config.h>
 
+__BEGIN_DECLS
 #include <arch/board/board.h>
+__END_DECLS
+#include <systemlib/systemlib.h>
 #include <drivers/device/i2c.h>
 
 #include <sys/types.h>
@@ -112,7 +115,6 @@
 #include <systemlib/perf_counter.h>
 #include <systemlib/err.h>
 
-#include <systemlib/systemlib.h>
 #include <poll.h>
 #include <uORB/uORB.h>
 #include <uORB/topics/vehicle_status.h>
@@ -486,15 +488,15 @@ BlinkM::led()
 
 		/* get number of used satellites in navigation */
 		num_of_used_sats = 0;
-		//for(int satloop=0; satloop<20; satloop++) {
-		for(int satloop=0; satloop<sizeof(vehicle_gps_position_raw.satellite_used); satloop++) {
+
+		for(unsigned satloop=0; satloop<sizeof(vehicle_gps_position_raw.satellite_used); satloop++) {
 			if(vehicle_gps_position_raw.satellite_used[satloop] == 1) {
 				num_of_used_sats++;
 			}
 		}
 
-		if(new_data_vehicle_status || no_data_vehicle_status < 3){
-			if(num_of_cells == 0) {
+		if (new_data_vehicle_status || no_data_vehicle_status < 3) {
+			if (num_of_cells == 0) {
 				/* looking for lipo cells that are connected */
 				printf("<blinkm> checking cells\n");
 				for(num_of_cells = 2; num_of_cells < 7; num_of_cells++) {
@@ -831,6 +833,8 @@ BlinkM::get_firmware_version(uint8_t version[2])
 	return transfer(&msg, sizeof(msg), version, 2);
 }
 
+void blinkm_usage();
+
 void blinkm_usage() {
 	fprintf(stderr, "missing command: try 'start', 'systemstate', 'ledoff', 'list' or a script name {options}\n");
 	fprintf(stderr, "options:\n");

src/drivers/drv_led.h

@@ -60,6 +60,6 @@ __BEGIN_DECLS
 /*
  * Initialise the LED driver.
  */
-__EXPORT extern void drv_led_start(void);
+__EXPORT void drv_led_start(void);
 
 __END_DECLS

src/drivers/led/led.cpp

@@ -117,4 +117,4 @@ drv_led_start(void)
 		if (gLED != nullptr)
 			gLED->init();
 	}
-}
+}