mtd: remove incorrect file name

This is an example of why it doesn't make much sense to put this
information here in the first place. I don't really know what purpose it
serves.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/devices/spear_smi.c

 /*
  * SMI (Serial Memory Controller) device driver for Serial NOR Flash on
  * SPEAr platform
- * The serial nor interface is largely based on drivers/mtd/m25p80.c,
- * however the SPI interface has been replaced by SMI.
+ * The serial nor interface is largely based on m25p80.c, however the SPI
+ * interface has been replaced by SMI.
  *
  * Copyright © 2010 STMicroelectronics.
  * Ashish Priyadarshi

drivers/mtd/nand/nand_base.c

 /*
- *  drivers/mtd/nand.c
- *
  *  Overview:
  *   This is the generic MTD driver for NAND flash devices. It should be
  *   capable of working with almost all NAND chips currently available.

drivers/mtd/nand/nand_bbt.c

 /*
- *  drivers/mtd/nand_bbt.c
- *
  *  Overview:
  *   Bad block table support for the NAND driver
  *

drivers/mtd/nand/nand_ids.c

 /*
- *  drivers/mtd/nandids.c
- *
  *  Copyright (C) 2002 Thomas Gleixner (tglx@linutronix.de)
  *
  * This program is free software; you can redistribute it and/or modify

drivers/mtd/nand/ndfc.c

 /*
- *  drivers/mtd/ndfc.c
- *
  *  Overview:
  *   Platform independent driver for NDFC (NanD Flash Controller)
  *   integrated into EP440 cores