powerpc/QorIQ: fix network frame manager TBI PHY address settings

TBI PHY address (TBIPA) register has been set in general frame manager
phy init funciton dtsec_init_phy() in drivers/net/fm/eth.c

So remove the duplicate code on QorIQ frame manager Ethernet related
platforms, which include Hydra board, P4080DS board and P2041rdb board.

Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Cc: Andy Fleming <afleming@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>