mmc: dw_mmc: convert copy of struct device in struct dw_mci to a reference

The 'struct dw_mci' maintains a copy of the pdev->dev instance instead of
maintaining a reference to that 'struct device' instance. Any resource
allocated using the device resource management kernel API with the instance
of 'struct device' in 'struct dw_mci' is then incorrect. Fix this by
converting the copy of 'struct device' in 'struct dw_mci' to a reference.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
index 7a7ebd3..a37a573 100644
--- a/include/linux/mmc/dw_mmc.h
+++ b/include/linux/mmc/dw_mmc.h
@@ -156,7 +156,7 @@
 	u32			fifoth_val;
 	u16			verid;
 	u16			data_offset;
-	struct device		dev;
+	struct device		*dev;
 	struct dw_mci_board	*pdata;
 	struct dw_mci_slot	*slot[MAX_MCI_SLOTS];