add FAT support for IDE, SCSI and USB

* Patches by Gleb Natapov, 2 Sep 2003:
  - cleanup of POST code for unsupported architectures
  - MPC824x locks way0 of data cache for use as initial RAM;
    this patch unlocks it after relocation to RAM and invalidates
    the locked entries.

* Patch by Gleb Natapov, 30 Aug 2003:
  new I2C driver for mpc107 bridge. Now works from flash.

* Patch by Dave Ellis, 11 Aug 2003:
  - JFFS2: fix typo in common/cmd_jffs2.c
  - JFFS2: fix CFG_JFFS2_SORT_FRAGMENTS option
  - JFFS2: remove node version 0 warning
  - JFFS2: accept JFFS2 PADDING nodes
  - SXNI855T: add AM29LV800 support
  - SXNI855T: move environment from EEPROM to flash
  - SXNI855T: boot from JFFS2 in NOR or NAND flash

* Patch by Bill Hargen, 11 Aug 2003:
  fixes for I2C on MPC8240
  - fix i2c_write routine
  - fix iprobe command
  - eliminates use of global variables, plus dead code, cleanup.