sky2: resume clocks

Change the resume path to use pci write config for a couple of reasons:
1. pci_write_config_dword() allows for more error
   checking of PCI health after resume.

2. better to toggle this register on all chip types, since that
   is what vendor driver does.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>