net: phylink: rearrange resolve mac_config() call

Use a boolean to indicate whether mac_config() should be called during
a resolution. This allows resolution to have a single location where
mac_config() will be called, which will allow us to make decisions
about how and what we do.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>