remoteproc/mediatek: fix sparse errors on dma_alloc and dma_free

Fixes the following sparse errors on dma_alloc_coherent() and
dma_free_coherent().

On drivers/remoteproc/mtk_scp.c:559:23:
warning: incorrect type in assignment (different address spaces)
   expected void [noderef] __iomem *cpu_addr
   got void *

On drivers/remoteproc/mtk_scp.c:572:56:
warning: incorrect type in argument 3 (different address spaces)
   expected void *cpu_addr
   got void [noderef] __iomem *cpu_addr

The cpu_addr is not a __iomem address.  Removes the marker.
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20201116082537.3287009-3-tzungbi@google.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/mtk_common.h

@@ -99,7 +99,7 @@ struct mtk_scp {
 	bool ipi_id_ack[SCP_IPI_MAX];
 	wait_queue_head_t ack_wq;
 
-	void __iomem *cpu_addr;
+	void *cpu_addr;
 	dma_addr_t dma_addr;
 	size_t dram_size;
 

drivers/remoteproc/mtk_scp.c

@@ -413,7 +413,7 @@ static void *scp_da_to_va(struct rproc *rproc, u64 da, size_t len)
 	} else if (scp->dram_size) {
 		offset = da - scp->dma_addr;
 		if (offset >= 0 && (offset + len) < scp->dram_size)
-			return (void __force *)scp->cpu_addr + offset;
+			return scp->cpu_addr + offset;
 	}
 
 	return NULL;