nand: Add common functions to linux/mtd/nand.h

Functions often used in SPL are now part of linux/mtd/nand.h.
Static modifiers are removed from these functions in
drivers/mtd/nand/nand_base.c.

Signed-off-by: Simon Schwarz <simonschwarzcor@gmail.com>
Cc: scottwood@freescale.com
Cc: s-paulraj@ti.com
Cc: albert.u.boot@aribaud.net
Acked-by: Scott Wood <scottwood@freescale.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 6aac6a2..27f6c77 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -133,7 +133,7 @@
  *
  * Default read function for 8bit buswith
  */
-static uint8_t nand_read_byte(struct mtd_info *mtd)
+uint8_t nand_read_byte(struct mtd_info *mtd)
 {
 	struct nand_chip *chip = mtd->priv;
 	return readb(chip->IO_ADDR_R);
@@ -196,7 +196,7 @@
  *
  * Default write function for 8bit buswith
  */
-static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 {
 	int i;
 	struct nand_chip *chip = mtd->priv;
@@ -249,7 +249,7 @@
  *
  * Default write function for 16bit buswith
  */
-static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
+void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 {
 	int i;
 	struct nand_chip *chip = mtd->priv;