uli526x: initialize the hardware prior to requesting interrupts

The firmware on MPC8610HPCD boards enables ULI ethernet and leaves it
in some funky state before booting Linux. For drivers, it's always good
idea to (re)initialize the hardware prior to requesting interrupts.

This patch fixes the following oops:

Oops: Kernel access of bad area, sig: 11 [#1]
MPC86xx HPCD
NIP: c0172820 LR: c017287c CTR: 00000000
[...]
NIP [c0172820] allocate_rx_buffer+0x2c/0xb0
LR [c017287c] allocate_rx_buffer+0x88/0xb0
Call Trace:
[df82bdc0] [c017287c] allocate_rx_buffer+0x88/0xb0 (unreliable)
[df82bde0] [c0173000] uli526x_interrupt+0xe4/0x49c
[df82be20] [c0045418] request_irq+0xf0/0x114
[df82be50] [c01737b0] uli526x_open+0x48/0x160
[df82be70] [c0201184] dev_open+0xb0/0xe8
[df82be80] [c0200104] dev_change_flags+0x90/0x1bc
[df82bea0] [c035fab0] ip_auto_config+0x214/0xef4
[df82bf60] [c03421c8] kernel_init+0xc4/0x2ac
[df82bff0] [c0010834] kernel_thread+0x44/0x60
Instruction dump:
4e800020 9421ffe0 7c0802a6 bfa10014 7c7e1b78 90010024 80030060 83e30054
2b80002f 419d0078 3fa0c039 48000058 <907f0010> 80630088 2f830000 419e0014

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>