igb: rename igb_ptp_enable to igb_ptp_feature_enable

The name igb_ptp_enable is not synonymous with the purpose of this
function, so rename it to better explain its purpose.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/igb/igb_ptp.c

@@ -360,7 +360,7 @@ static int igb_ptp_settime_i210(struct ptp_clock_info *ptp,
 	return 0;
 }
 
-static int igb_ptp_enable(struct ptp_clock_info *ptp,
+static int igb_ptp_feature_enable(struct ptp_clock_info *ptp,
 				  struct ptp_clock_request *rq, int on)
 {
 	return -EOPNOTSUPP;
@@ -745,7 +745,7 @@ void igb_ptp_init(struct igb_adapter *adapter)
 		adapter->ptp_caps.adjtime = igb_ptp_adjtime_82576;
 		adapter->ptp_caps.gettime = igb_ptp_gettime_82576;
 		adapter->ptp_caps.settime = igb_ptp_settime_82576;
-		adapter->ptp_caps.enable = igb_ptp_enable;
+		adapter->ptp_caps.enable = igb_ptp_feature_enable;
 		adapter->cc.read = igb_ptp_read_82576;
 		adapter->cc.mask = CLOCKSOURCE_MASK(64);
 		adapter->cc.mult = 1;
@@ -765,7 +765,7 @@ void igb_ptp_init(struct igb_adapter *adapter)
 		adapter->ptp_caps.adjtime = igb_ptp_adjtime_82576;
 		adapter->ptp_caps.gettime = igb_ptp_gettime_82576;
 		adapter->ptp_caps.settime = igb_ptp_settime_82576;
-		adapter->ptp_caps.enable = igb_ptp_enable;
+		adapter->ptp_caps.enable = igb_ptp_feature_enable;
 		adapter->cc.read = igb_ptp_read_82580;
 		adapter->cc.mask = CLOCKSOURCE_MASK(IGB_NBITS_82580);
 		adapter->cc.mult = 1;
@@ -784,7 +784,7 @@ void igb_ptp_init(struct igb_adapter *adapter)
 		adapter->ptp_caps.adjtime = igb_ptp_adjtime_i210;
 		adapter->ptp_caps.gettime = igb_ptp_gettime_i210;
 		adapter->ptp_caps.settime = igb_ptp_settime_i210;
-		adapter->ptp_caps.enable = igb_ptp_enable;
+		adapter->ptp_caps.enable = igb_ptp_feature_enable;
 		/* Enable the timer functions by clearing bit 31. */
 		wr32(E1000_TSAUXC, 0x0);
 		break;