include: linux: mtd: Remove duplicate include of nand.h

linux/mtd/nand.h has been included at line 17.
So we remove the duplicate one at line 21.

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210323031737.259365-1-wanjiabing@vivo.com

Author: Wan Jiabing

include/linux/mtd/rawnand.h

@@ -18,7 +18,6 @@
 #include <linux/mtd/flashchip.h>
 #include <linux/mtd/bbm.h>
 #include <linux/mtd/jedec.h>
-#include <linux/mtd/nand.h>
 #include <linux/mtd/onfi.h>
 #include <linux/mutex.h>
 #include <linux/of.h>