boards/nucleo-wl55jc: Fix Arduino SPI bus

The macro `ARDUINO_SPI_D11D12D13` is used to refer to the SPI bus
on the pins D11/D12/D13 on Arduino UNO compatible boards. For all
Nucleo64 boards this is `SPI_DEV(0)`, but for this board `SPI_DEV(0)`
is internally connected to the radio. Instead `SPI_DEV(1)` is connected
to the correct pins. This provides the macro explicitly in
`periph_conf.h`, which takes preference over the fallback in
`boards/common/nucleo64` when provided.

boards/nucleo-wl55jc/include/periph_conf.h

@@ -117,7 +117,12 @@ static const spi_conf_t spi_config[] = {
 #endif
 };
 
-#define SPI_NUMOF           ARRAY_SIZE(spi_config)
+#define SPI_NUMOF               ARRAY_SIZE(spi_config)
+/**
+ * @brief   Provide ARDUINO_SPI_D11D12D13 explicitly, as the first SPI
+ *          interface is connected to the radio.
+ */
+#define ARDUINO_SPI_D11D12D13   SPI_DEV(1)
 /** @} */
 
 /**