stm32: f24: dma: clarify stream/channel

It's always stream on the "new" dma controller (unless it's channel....)

Fix a couple of inconsistent prototypes that had carried over from f1
originally.  Reported by vampi on irc.

include/libopencm3/stm32/common/dma_common_f24.h

@@ -580,9 +580,9 @@ void dma_set_memory_size(uint32_t dma, uint8_t stream, uint32_t mem_size);
 void dma_set_peripheral_size(uint32_t dma, uint8_t stream,
 			     uint32_t peripheral_size);
 void dma_enable_memory_increment_mode(uint32_t dma, uint8_t stream);
-void dma_disable_memory_increment_mode(uint32_t dma, uint8_t channel);
+void dma_disable_memory_increment_mode(uint32_t dma, uint8_t stream);
 void dma_enable_peripheral_increment_mode(uint32_t dma, uint8_t stream);
-void dma_disable_peripheral_increment_mode(uint32_t dma, uint8_t channel);
+void dma_disable_peripheral_increment_mode(uint32_t dma, uint8_t stream);
 void dma_enable_fixed_peripheral_increment_mode(uint32_t dma, uint8_t stream);
 void dma_enable_circular_mode(uint32_t dma, uint8_t stream);
 void dma_channel_select(uint32_t dma, uint8_t stream, uint32_t channel);