dmaengine: Remove device_prep_dma_imm_data from struct dma_device

The device_prep_dma_imm_data() method isn't implemented or invoked by
any code since commit 80ade22 ("misc: mic: remove the MIC drivers").

Remove it, shrinking struct dma_device by a few bytes.

Signed-off-by: Nathan Lynch <nathan.lynch@amd.com>
Link: https://lore.kernel.org/r/20250210-dmaengine-drop-imm-data-v1-1-e017766da2fa@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: nathanlynch

include/linux/dmaengine.h

@@ -839,7 +839,6 @@ struct dma_filter {
  *	The function takes a buffer of size buf_len. The callback function will
  *	be called after period_len bytes have been transferred.
  * @device_prep_interleaved_dma: Transfer expression in a generic way.
- * @device_prep_dma_imm_data: DMA's 8 byte immediate data to the dst address
  * @device_caps: May be used to override the generic DMA slave capabilities
  *	with per-channel specific ones
  * @device_config: Pushes a new configuration to a channel, return 0 or an error
@@ -942,9 +941,6 @@ struct dma_device {
 	struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
 		struct dma_chan *chan, struct dma_interleaved_template *xt,
 		unsigned long flags);
-	struct dma_async_tx_descriptor *(*device_prep_dma_imm_data)(
-		struct dma_chan *chan, dma_addr_t dst, u64 data,
-		unsigned long flags);
 
 	void (*device_caps)(struct dma_chan *chan, struct dma_slave_caps *caps);
 	int (*device_config)(struct dma_chan *chan, struct dma_slave_config *config);