sdio: support IO_RW_EXTENDED

Support the multi-byte transfer operation, including handlers for
common operations like writel()/readl().

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/core/sdio_ops.h b/drivers/mmc/core/sdio_ops.h
index f0e9d69..1d42e4f3 100644
--- a/drivers/mmc/core/sdio_ops.h
+++ b/drivers/mmc/core/sdio_ops.h
@@ -15,6 +15,8 @@
 int mmc_send_io_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr);
 int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
 	unsigned addr, u8 in, u8* out);
+int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
+	unsigned addr, int bang, u8 *data, unsigned size);
 
 #endif