powerpc/eeh: Update VF config space after EEH

Add EEH platform operations for pseries to update VF config space.
With this change after EEH, the VF will have updated config space for
pseries platform.

Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: Juan J. Alvarez <jjalvare@linux.vnet.ibm.com>
Acked-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>