[SPI] Set Handle state only the first time

Fix #133

Signed-off-by: Frederic.Pillon <frederic.pillon@st.com>

Author: fpistm

cores/arduino/stm32/spi_com.c

@@ -222,7 +222,6 @@ void spi_init(spi_t *obj, uint32_t speed, spi_mode_e mode, uint8_t msb)
   /* Fill default value */
   handle->Instance               = obj->spi;
   handle->Init.Mode              = SPI_MODE_MASTER;
-  handle->State                  = HAL_SPI_STATE_RESET;
 
   spi_freq = spi_getClkFreqInst(obj->spi);
   if(speed >= (spi_freq/SPI_SPEED_CLOCK_DIV2_MHZ)) {

libraries/SPI/src/SPI.cpp

@@ -65,6 +65,7 @@ void SPIClass::begin(uint8_t _pin)
     digitalWrite(_pin, HIGH);
   }
 
+  _spi.handle.State = HAL_SPI_STATE_RESET;
   spi_init(&_spi, spiSettings[idx].clk,
                   spiSettings[idx].dMode,
                   spiSettings[idx].msb);