igb: Remove duplicate defines

There's no need to define same thing twice.

Signed-off-by: Kai-Heng Feng <[e-mail]>
Signed-off-by: Tony Nguyen <[e-mail]>

drivers/net/ethernet/intel/igb/e1000_defines.h

···
 #define E1000_VFTA_ENTRY_MASK                0x7F
 #define E1000_VFTA_ENTRY_BIT_SHIFT_MASK      0x1F
 
-/* DMA Coalescing register fields */
-#define E1000_PCIEMISC_LX_DECISION      0x00000080 /* Lx power on DMA coal */
-
 /* Tx Rate-Scheduler Config fields */
 #define E1000_RTTBCNRC_RS_ENA		0x80000000
 #define E1000_RTTBCNRC_RF_DEC_MASK	0x00003FFF

drivers/net/ethernet/intel/igb/e1000_regs.h

···
 #define E1000_DMCRTRH	0x05DD0 /* Receive Packet Rate Threshold */
 #define E1000_DMCCNT	0x05DD4 /* Current Rx Count */
 #define E1000_FCRTC	0x02170 /* Flow Control Rx high watermark */
-#define E1000_PCIEMISC	0x05BB8 /* PCIE misc config register */
 
 /* TX Rate Limit Registers */
 #define E1000_RTTDQSEL	0x3604 /* Tx Desc Plane Queue Select - WO */