[POWERPC] mpc5200: Amalgamated DTS fixes and updates

DTS updates that fix booting problems on mpc5200-based boards:
- change to ethernet reg property
- addition of mdio and phy nodes
- removal of pci node (Motion-Pro board)

Other DTS updates:
- update i2c device tree nodes
- add lpb bus node and flash device (without partitions defined)
- add rtc i2c nodes

Signed-off-by: Marian Balakowicz <m8@semihalf.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>