wiring_private.h: update DMA map to reflect static default use

Author: GrumpyOldPizza

cores/stm32l4/wiring_private.h

@@ -64,8 +64,8 @@ extern "C" {
  * DMA_CHANNEL_DMA1_CH1_ADC1
  * DMA_CHANNEL_DMA1_CH2_USART3_TX
  * DMA_CHANNEL_DMA1_CH3_USART3_RX
- * DMA_CHANNEL_DMA1_CH4_DFSDM0
- * DMA_CHANNEL_DMA1_CH5_DFSDM1
+ * DMA_CHANNEL_DMA1_CH4_SPI2_RX / DMA_CHANNEL_DMA1_CH4_DFSDM0
+ * DMA_CHANNEL_DMA1_CH5_SPI2_TX / DMA_CHANNEL_DMA1_CH5_DFSDM1 
  * DMA_CHANNEL_DMA1_CH6_SAI2_A
  * DMA_CHANNEL_DMA1_CH7_I2C1_RX
  * DMA_CHANNEL_DMA2_CH1_SPI3_RX