e1000e: Rename a variable in e1000e_receive_internal()

Rename variable "n" to "causes", which properly represents the content
of the variable.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

hw/net/e1000e_core.c

@@ -1650,7 +1650,7 @@ static ssize_t
 e1000e_receive_internal(E1000ECore *core, const struct iovec *iov, int iovcnt,
                         bool has_vnet)
 {
-    uint32_t n = 0;
+    uint32_t causes = 0;
     uint8_t buf[ETH_ZLEN];
     struct iovec min_iov;
     size_t size, orig_size;
@@ -1723,32 +1723,32 @@ e1000e_receive_internal(E1000ECore *core, const struct iovec *iov, int iovcnt,
 
         /* Perform small receive detection (RSRPD) */
         if (total_size < core->mac[RSRPD]) {
-            n |= E1000_ICS_SRPD;
+            causes |= E1000_ICS_SRPD;
         }
 
         /* Perform ACK receive detection */
         if  (!(core->mac[RFCTL] & E1000_RFCTL_ACK_DIS) &&
              (e1000e_is_tcp_ack(core, core->rx_pkt))) {
-            n |= E1000_ICS_ACK;
+            causes |= E1000_ICS_ACK;
         }
 
         /* Check if receive descriptor minimum threshold hit */
         rdmts_hit = e1000e_rx_descr_threshold_hit(core, rxr.i);
-        n |= e1000e_rx_wb_interrupt_cause(core, rxr.i->idx, rdmts_hit);
+        causes |= e1000e_rx_wb_interrupt_cause(core, rxr.i->idx, rdmts_hit);
 
         trace_e1000e_rx_written_to_guest(rxr.i->idx);
     } else {
-        n |= E1000_ICS_RXO;
+        causes |= E1000_ICS_RXO;
         retval = 0;
 
         trace_e1000e_rx_not_written_to_guest(rxr.i->idx);
     }
 
-    if (!e1000e_intrmgr_delay_rx_causes(core, &n)) {
-        trace_e1000e_rx_interrupt_set(n);
-        e1000e_set_interrupt_cause(core, n);
+    if (!e1000e_intrmgr_delay_rx_causes(core, &causes)) {
+        trace_e1000e_rx_interrupt_set(causes);
+        e1000e_set_interrupt_cause(core, causes);
     } else {
-        trace_e1000e_rx_interrupt_delayed(n);
+        trace_e1000e_rx_interrupt_delayed(causes);
     }
 
     return retval;