dmaengine: mmp_pdma: Remove mmp_pdma_filter_fn()

It's not used anywhere -- drop it.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20210121110356.1768635-2-lkundrak@v3.skSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/mmp_pdma.c

@@ -18,7 +18,6 @@
 #include <linux/of_device.h>
 #include <linux/of_dma.h>
 #include <linux/of.h>
-#include <linux/dma/mmp-pdma.h>
 
 #include "dmaengine.h"
 
@@ -1148,19 +1147,6 @@ static struct platform_driver mmp_pdma_driver = {
 	.remove		= mmp_pdma_remove,
 };
 
-bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
-{
-	struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
-
-	if (chan->device->dev->driver != &mmp_pdma_driver.driver)
-		return false;
-
-	c->drcmr = *(unsigned int *)param;
-
-	return true;
-}
-EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn);
-
 module_platform_driver(mmp_pdma_driver);
 
 MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");

include/linux/dma/mmp-pdma.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _MMP_PDMA_H_
-#define _MMP_PDMA_H_
-
-struct dma_chan;
-
-#ifdef CONFIG_MMP_PDMA
-bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param);
-#else
-static inline bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
-{
-	return false;
-}
-#endif
-
-#endif /* _MMP_PDMA_H_ */