mmc: at91_mci: correct kunmap_atomic()

kunmap_atomic() accepts a pointer to any location in the page so we do not
need the subtraction and cast.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Wolfgang Muees <wolfgang.mues@auerswald.de>
Cc: Andrew Victor <avictor.za@gmail.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/mmc/host/at91_mci.c

@@ -248,7 +248,7 @@ static inline void at91_mci_sg_to_dma(struct at91mci_host *host, struct mmc_data
 			dmabuf = (unsigned *)tmpv;
 		}
 
-		kunmap_atomic(((void *)sgbuffer) - sg->offset, KM_BIO_SRC_IRQ);
+		kunmap_atomic(sgbuffer, KM_BIO_SRC_IRQ);
 
 		if (size == 0)
 			break;
@@ -313,7 +313,7 @@ static void at91_mci_post_dma_read(struct at91mci_host *host)
 			dmabuf = (unsigned *)tmpv;
 		}
 
-		kunmap_atomic(((void *)sgbuffer)-sg->offset, KM_BIO_SRC_IRQ);
+		kunmap_atomic(sgbuffer, KM_BIO_SRC_IRQ);
 		dmac_flush_range((void *)sgbuffer, ((void *)sgbuffer) + amount);
 		data->bytes_xfered += amount;
 		if (size == 0)