Fix bug with PWM choosing pin number for Raspberry Pi.

Author: tdicola

Adafruit_GPIO/PWM.py

@@ -46,7 +46,7 @@ def start(self, pin, dutycycle, frequency_hz=2000):
 		if dutycycle < 0.0 or dutycycle > 100.0:
 			raise ValueError('Invalid duty cycle value, must be between 0.0 to 100.0 (inclusive).')
 		# Make pin an output.
-		self.rpi_gpio.setup(12, self.rpi_gpio.OUT)
+		self.rpi_gpio.setup(pin, self.rpi_gpio.OUT)
 		# Create PWM instance and save a reference for later access.
 		self.pwm[pin] = self.rpi_gpio.PWM(pin, frequency_hz)
 		# Start the PWM at the specified duty cycle.