ASoC: loongson: fix address space confusion

The i2s driver uses the mapped __iomem address of the FIFO as the DMA
address for the device. This apparently works on loongarch because of
the way it handles __iomem pointers as aliases of physical addresses,
but this is not portable to other architectures and causes a compiler
warning when dma addresses are not the same size as pointers:

sound/soc/loongson/loongson_i2s_pci.c: In function 'loongson_i2s_pci_probe':
sound/soc/loongson/loongson_i2s_pci.c:110:29: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
110 | tx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_TX_DATA;
| ^
sound/soc/loongson/loongson_i2s_pci.c:113:29: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
113 | rx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_RX_DATA;
| ^

Change the driver to instead use the physical address as stored in the
PCI BAR resource directly. Since 'dev_addr' is a 32-bit address, I think
this results in the same truncated address on loongarch but is otherwise
closer to portable code and avoids the warning.

Fixes: d84881e06836d ("ASoC: Add support for Loongson I2S controller")
Signed-off-by: Arnd Bergmann <[e-mail]>
Link: https://lore.kernel.org/r/Message-Id: <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/loongson/loongson_i2s_pci.c

···
 	tx_data = &i2s->tx_dma_data;
 	rx_data = &i2s->rx_dma_data;
 
-	tx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_TX_DATA;
+	tx_data->dev_addr = pci_resource_start(pdev, 0) + LS_I2S_TX_DATA;
 	tx_data->order_addr = i2s->reg_base + LS_I2S_TX_ORDER;
 
-	rx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_RX_DATA;
+	rx_data->dev_addr = pci_resource_start(pdev, 0) + LS_I2S_RX_DATA;
 	rx_data->order_addr = i2s->reg_base + LS_I2S_RX_ORDER;
 
 	tx_data->irq = fwnode_irq_get_byname(fwnode, "tx");