mmc: dw_mmc: Fix mask in IDMAC_SET_BUFFER1_SIZE macro

The mask used inside this macro was assuming Buffer_Size1's [BS1's]
width to be 14 bits, it is actually 13 bits.  Modify masks used in
IDMAC_SET_BUFFER1_SIZE such that they use only 13 bits instead of
current 14.

Signed-off-by: Shashidhar Hiremath <shashidharh@vayavyalabs.com>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 77f0b6b..f13bb49 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -62,7 +62,7 @@
 
 	u32		des1;	/* Buffer sizes */
 #define IDMAC_SET_BUFFER1_SIZE(d, s) \
-	((d)->des1 = ((d)->des1 & 0x03ffc000) | ((s) & 0x3fff))
+	((d)->des1 = ((d)->des1 & 0x03ffe000) | ((s) & 0x1fff))
 
 	u32		des2;	/* buffer 1 physical address */