MTD: NAND: mxs_nand_init_dma: Make mxs_nand_init_dma static

mxs_nand_init_dma is only referenced from mxs_nand.c.  It's not
referenced in any headers or outside code, so this patch
defines it as static.

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/drivers/mtd/nand/raw/mxs_nand.c b/drivers/mtd/nand/raw/mxs_nand.c
index 2d84bff..eff8523 100644
--- a/drivers/mtd/nand/raw/mxs_nand.c
+++ b/drivers/mtd/nand/raw/mxs_nand.c
@@ -1092,7 +1092,7 @@
 /*
  * Initializes the NFC hardware.
  */
-int mxs_nand_init_dma(struct mxs_nand_info *info)
+static int mxs_nand_init_dma(struct mxs_nand_info *info)
 {
 	int i = 0, j, ret = 0;