nand_spl: Fix large page nand_command()

This patch changes the large page nand_command() routine to use a word
offset instead of a byte offset. The 'offs' argument gets divided by 2
so that the offset passed to nand_command() is still by byte offset.
Originally, the offset was not shifted and when too high an offset was
requested the nand chip would attempt to read non-existent data.
Signed-off-by: NAlex Waterman <awaterman@dawning.com>

nand_spl/nand_boot.c

@@ -90,6 +90,10 @@ static int nand_command(struct mtd_info *mtd, int block, int page, int offs, u8
 		cmd = NAND_CMD_READ0;
 	}
 
+	/* Shift the offset from byte addressing to word addressing. */
+	if (this->options & NAND_BUSWIDTH_16)
+		offs >>= 1;
+
 	/* Begin command latch cycle */
 	this->cmd_ctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);
 	/* Set ALE and clear CLE to start address cycle */