net: macb: undo operations in case of failure

Undo previously done operation in case macb_phylink_connect()
fails. Since macb_reset_hw() is the 1st undo operation the
napi_exit label was renamed to reset_hw.

Fixes: 7897b071 ("net: macb: convert to phylink")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>