Merged in Oblivium/librepilot/LP-533_Fix_serial_receiver_input_on_Sparky2 (pull request #441)

LP-533 incorrect MCU pin used to toggle inverter for rcvr port on Sparky2

Approved-by: Vladimir Zidar <mr_w@mindnever.org>
Approved-by: Jan NIJS <dr.oblivium@gmail.com>
Approved-by: Philippe Renon <philippe_renon@yahoo.fr>
Approved-by: Lalanne Laurent <f5soh@free.fr>
Approved-by: Brian Webb <webbbn@gmail.com>
Approved-by: Alessio Morale <alessiomorale@gmail.com>

Author: dr-oblivium

flight/targets/boards/sparky2/pios_board.h

@@ -145,7 +145,7 @@ extern uint32_t pios_i2c_flexiport_adapter_id;
 // Inverter for SBUS handling
 #define PIOS_USART_INVERTER_PORT    USART6
 #define PIOS_USART_INVERTER_GPIO    GPIOC
-#define PIOS_USART_INVERTER_PIN     GPIO_Pin_4
+#define PIOS_USART_INVERTER_PIN     GPIO_Pin_6
 #define PIOS_USART_INVERTER_ENABLE  Bit_SET
 #define PIOS_USART_INVERTER_DISABLE Bit_RESET