i5100_edac: probe for device 19 function 0

Probe and store the device handle for the device 19 function 0 during
driver initialization. The device is used during fault injection.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ericsson.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>