Wire and SPI Init: move to sketch system.pde from libraries

* Wire.begin removed from AP_Baro_BMP085::init()
* SPI.begin  removed from AP_Baro_MS5611::init()
* SPI.begin  removed from AP_InertialSensor_MPU6000::hardware_init()

* Both Wire.begin and SPI.begin added very early in init_ardupilot in
  ArduCopter/system.pde and ArduPlane/system.pde

ArduCopter/system.pde

@@ -103,6 +103,12 @@ static void init_ardupilot()
 						 "\n\nFree RAM: %u\n"),
                     memcheck_available_memory());
 
+	//
+	// Initialize Wire and SPI libraries
+	//
+    Wire.begin();
+    SPI.begin();
+    SPI.setClockDivider(SPI_CLOCK_DIV16); // 1MHZ SPI rate
 	//
 	// Initialize the isr_registry.
 	//

ArduPlane/system.pde

@@ -100,6 +100,12 @@ static void init_ardupilot()
 						 "\n\nFree RAM: %u\n"),
                     memcheck_available_memory());
 
+	//
+	// Initialize Wire and SPI libraries
+	//
+    Wire.begin();
+    SPI.begin();
+    SPI.setClockDivider(SPI_CLOCK_DIV16); // 1MHZ SPI rate
 	//
 	// Initialize the ISR registry.
 	//

libraries/AP_Baro/AP_Baro_BMP085.cpp

@@ -64,8 +64,6 @@ bool AP_Baro_BMP085::init(int initialiseWireLib, bool apm2_hardware)
 
 	pinMode(BMP085_EOC, INPUT);	 // End Of Conversion (PC7) input
 
-	if( initialiseWireLib != 0 )
-			Wire.begin();
 
 	oss = 3;					 // Over Sampling setting 3 = High resolution
 	BMP085_State = 0;		 // Initial state

libraries/AP_Baro/AP_Baro_MS5611.cpp

@@ -115,12 +115,6 @@ uint8_t AP_Baro_MS5611::MS5611_Ready()
 // SPI should be initialized externally
 void AP_Baro_MS5611::init()
 {
-    SPI.begin();
-    #if F_CPU == 16000000
-    SPI.setClockDivider(SPI_CLOCK_DIV16);
-    #else
-    # error MS5611 requires SPI at 1MHZ! Need appropriate SPI clock divider
-    #endif
 	pinMode(MS5611_CS, OUTPUT);	 // Chip select Pin
     digitalWrite(MS5611_CS, HIGH);
     delay(1);

libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp

@@ -248,14 +248,6 @@ void AP_InertialSensor_MPU6000::register_write(uint8_t reg, uint8_t val)
 
 void AP_InertialSensor_MPU6000::hardware_init()
 {
-    // Need to initialize SPI if it hasn't already.
-    SPI.begin();
-    #if F_CPU == 16000000
-    SPI.setClockDivider(SPI_CLOCK_DIV16); // SPI at 1MHz
-    #else
-    # error MPU6000 requires SPI at 1MHZ! Need appropriate SPI clock divider.
-    #endif
-
     // MPU6000 chip select setup
     pinMode(_cs_pin, OUTPUT);
     digitalWrite(_cs_pin, HIGH);