ARM: LPC32xx: Remove USB and I2C init from phy3250.c

USB and I2C initialization can be removed safely from the board specific
phy3250.c, now that initialization moved to the generalized clock.c.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Tested-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>