powerpc/83xx: Fix style problems in usb.c and remove unneccessary includes from mpc83xx.h

Replace printk(KERN_WARN with pr_warn(

Remove a couple of blank lines

Re-align multi-line code.

Replace asm/io.h by linux/io.h

mpc83xx.h doesn't need linux/device.h or asm/pci-bridge.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/2cb498f637e082a4af8032311fad3cae84d6aa5d.1692199324.git.christophe.leroy@csgroup.eu