Fix SPI pin assignment and Settings not applied

Should we use a TXbuffer anyway to enqueue transfers?

Author: facchinm

libraries/SPI/SPI.cpp

@@ -48,7 +48,7 @@ void arduino::MbedSPI::detachInterrupt() {
 }
 
 void arduino::MbedSPI::begin() {
-    dev = new mbed::SPI((PinName)_miso, (PinName)_mosi, (PinName)_sck);
+    dev = new mbed::SPI((PinName)_mosi, (PinName)_miso, (PinName)_sck);
 }
 
 void arduino::MbedSPI::end() {

libraries/SPI/SPI.h

@@ -25,7 +25,7 @@ class MbedSPI : public SPIClass
     virtual void end();
 
 private:
-    SPISettings settings;
+    SPISettings settings = SPISettings(0, MSBFIRST, SPI_MODE0);
     mbed::SPI* dev;
     int _miso;
     int _mosi;