ERROR macro: get rid of the many 'oddly, ERROR is not defined for c++', use PX4_ERROR

src/drivers/px4flow/px4flow.cpp

@@ -40,6 +40,7 @@
  */
 
 #include <px4_config.h>
+#include <px4_defines.h>
 
 #include <drivers/device/i2c.h>
 
@@ -90,12 +91,6 @@
 #define PX4FLOW_MAX_DISTANCE 5.0f
 #define PX4FLOW_MIN_DISTANCE 0.3f
 
-/* oddly, ERROR is not defined for c++ */
-#ifdef ERROR
-# undef ERROR
-#endif
-static const int ERROR = -1;
-
 #ifndef CONFIG_SCHED_WORKQUEUE
 # error This requires CONFIG_SCHED_WORKQUEUE.
 #endif
@@ -226,7 +221,7 @@ PX4FLOW::~PX4FLOW()
 int
 PX4FLOW::init()
 {
-	int ret = ERROR;
+	int ret = PX4_ERROR;
 
 	/* do I2C init (and probe) first */
 	if (I2C::init() != OK) {
@@ -663,12 +658,6 @@ PX4FLOW::print_info()
 namespace px4flow
 {
 
-/* oddly, ERROR is not defined for c++ */
-#ifdef ERROR
-# undef ERROR
-#endif
-const int ERROR = -1;
-
 PX4FLOW	*g_dev = nullptr;
 bool start_in_progress = false;