phy: marvell: Fix 88E1510 initialization

A bug was introduced in the merge commit b6333531 ("Merge
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net"

)
The generic marvell_config_init (and therefore marvell_of_reg_init) is
not called anymore for the Marvell 88E1510 (in net-next).

This patch calls marvell_config_init and moves the specific init
function for the 88E1510 below the marvell_config_init function to avoid
adding a function predeclaration.

Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: David S. Miller <davem@davemloft.net>