e1000: cleanup CE4100 MDIO registers access

A global variable is currently used to hold the virtual address of the
CE4100 MDIO base register address. Store the address in the e1000_hw
structure and update macros accordingly.

Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/intel/e1000/e1000_hw.h b/drivers/net/ethernet/intel/e1000/e1000_hw.h
index cf7e3c0..f6c4d7e 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_hw.h
+++ b/drivers/net/ethernet/intel/e1000/e1000_hw.h
@@ -812,8 +812,7 @@
 #define E1000_FLA      0x0001C	/* Flash Access - RW */
 #define E1000_MDIC     0x00020	/* MDI Control - RW */
 
-extern void __iomem *ce4100_gbe_mdio_base_virt;
-#define INTEL_CE_GBE_MDIO_RCOMP_BASE    (ce4100_gbe_mdio_base_virt)
+#define INTEL_CE_GBE_MDIO_RCOMP_BASE    (hw->ce4100_gbe_mdio_base_virt)
 #define E1000_MDIO_STS  (INTEL_CE_GBE_MDIO_RCOMP_BASE + 0)
 #define E1000_MDIO_CMD  (INTEL_CE_GBE_MDIO_RCOMP_BASE + 4)
 #define E1000_MDIO_DRV  (INTEL_CE_GBE_MDIO_RCOMP_BASE + 8)
@@ -1343,6 +1342,7 @@
 struct e1000_hw {
 	u8 __iomem *hw_addr;
 	u8 __iomem *flash_address;
+	void __iomem *ce4100_gbe_mdio_base_virt;
 	e1000_mac_type mac_type;
 	e1000_phy_type phy_type;
 	u32 phy_init_script;