AP_Baro: unify singleton naming to _singleton and get_singleton()

libraries/AP_Baro/AP_Baro.cpp

@@ -165,14 +165,14 @@ const AP_Param::GroupInfo AP_Baro::var_info[] = {
 };
 
 // singleton instance
-AP_Baro *AP_Baro::_instance;
+AP_Baro *AP_Baro::_singleton;
 
 /*
   AP_Baro constructor
  */
 AP_Baro::AP_Baro()
 {
-    _instance = this;
+    _singleton = this;
 
     AP_Param::setup_object_defaults(this, var_info);
 }
@@ -707,7 +707,7 @@ void AP_Baro::_probe_i2c_barometers(void)
 
 bool AP_Baro::should_df_log() const
 {
-    AP_Logger *instance = AP_Logger::instance();
+    AP_Logger *instance = AP_Logger::get_singleton();
     if (instance == nullptr) {
         return false;
     }
@@ -841,7 +841,7 @@ namespace AP {
 
 AP_Baro &baro()
 {
-    return *AP_Baro::get_instance();
+    return *AP_Baro::get_singleton();
 }
 
 };

libraries/AP_Baro/AP_Baro.h

@@ -31,8 +31,8 @@ public:
     AP_Baro &operator=(const AP_Baro&) = delete;
 
     // get singleton
-    static AP_Baro *get_instance(void) {
-        return _instance;
+    static AP_Baro *get_singleton(void) {
+        return _singleton;
     }
 
     // barometer types
@@ -183,7 +183,7 @@ public:
 
 private:
     // singleton
-    static AP_Baro *_instance;
+    static AP_Baro *_singleton;
     
     // how many drivers do we have?
     uint8_t _num_drivers;