bnx2x: Split PHY functions

Move the code into PHY oriented functions, and for that a new structure
is defines for each PHY which contain PHY properties and its own
functions. This also enables to encapsulate all PHY specific operations
into the PHY functions. During initialization, the PHYs will be probed
by the "bnx2x_phy_probe" function to detect which PHYs exist on-board,
and configure them accordingly. Note that the ext_phy_reset
implementation was incorporated in the ext_phy_init since it is actually
part of the PHY initialization procedure.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>