85xx/b4:Correct USB DR controller liodn entry

85xx/b4:Correct USB DR controller liodn entry

LIODN entry for B4860/B4420 mentions USB controller as "mph"
insread of "dr". This results in PAMU not permitting bus
transactions for USB DR controller on B4860 resulting in
USB function failure. Replacing "fsl-usb2-mph" with
"fsl-usb2-dr" allows USB DR controller bus transactions

Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com>
Reviewed-by: Sethi Varun-B16395 <Varun.Sethi@freescale.com>
Reviewed-by: Sun Yusong-R58495 <yorksun@freescale.com>