stmmac: let stmmac_dvr_probe take a struct of resources

Creat a struct that contain all the resources that needs to be
assigned to the priv struct in stmmac_dvr_probe. This makes it
possible to factor out more common code from the other probe
functions and also use this struct to hold the resources as
they are fetched.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>