spi: dw-dma: decrease reference count in dw_spi_dma_init_mfld()

pci_get_device() will increase the reference count for the returned
pci_dev. Since 'dma_dev' is only used to filter the channel in
dw_spi_dma_chan_filer() after using it we need to call pci_dev_put() to
decrease the reference count. Also add pci_dev_put() for the error case.

Fixes: 7063c0d9 ("spi/dw_spi: add DMA support")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20221116093204.46700-1-wangxiongfeng2@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-dw-dma.c

@@ -128,12 +128,15 @@ static int dw_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws)
 
 	dw_spi_dma_sg_burst_init(dws);
 
+	pci_dev_put(dma_dev);
+
 	return 0;
 
 free_rxchan:
 	dma_release_channel(dws->rxchan);
 	dws->rxchan = NULL;
 err_exit:
+	pci_dev_put(dma_dev);
 	return -EBUSY;
 }