igc: Clean up the mac_info structure

collision_delta, tx_packet_delta, txcw, adaptive_ifs and
has_fwsm fields not in use.
This patch come to clean up the driver code.
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/igc/igc_hw.h

@@ -82,10 +82,7 @@ struct igc_mac_info {
 
 	enum igc_mac_type type;
 
-	u32 collision_delta;
 	u32 mc_filter_type;
-	u32 tx_packet_delta;
-	u32 txcw;
 
 	u16 mta_reg_count;
 	u16 uta_reg_count;
@@ -95,8 +92,6 @@ struct igc_mac_info {
 
 	u8 forced_speed_duplex;
 
-	bool adaptive_ifs;
-	bool has_fwsm;
 	bool asf_firmware_present;
 	bool arc_subsystem_valid;