powerpc/mpc5121: update mpc5121ads DTS

Collects several changes needed after applying
previous mpc5121 platform and driver patches:

- Add mpc5121 reset module node
- Clean up and fix NAND description, remove unused properties
  here and correct NAND flash chip size.
- Clean up I2C nodes: remove obsolete "cell-index" properties,
  add "fsl,preserve-clocking" property
- Add I2C RTC node for m41t61 RTC
- Add I2C nodes for AD7414 temperature sensor and AT24C32CD3 EEPROM
- Fix compatible property in DMA node
- Clean up CAN nodes, remove unused "cell-index" properties
- Fix compatible property in DIU node
- USB node changes:
    - use "fsl,mpc5121-usb2-dr" compatible property only
    - remove "port0" and "port1" properties as these are only used
      for multi-port host(MHP) module which is not available
      on MPC5121.
    - use 'fsl,invert-drvvbus' and 'fsl,invert-pwr-fault' in
      USB node for internal PHY to specify polarities
      of the appropriate port pins.

Signed-off-by: Piotr Ziecik <kosmo@semihalf.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Detlev Zundel <dzu@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>