net: batch of last_rx update avoidance in ethernet drivers.

None of those drivers uses last_rx for its own needs.

See 4dc89133f4 ("net: add a comment on
netdev->last_rx") for reference.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Zhangfei Gao <zhangfei.gao@linaro.org>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Wingman Kwok <w-kwok2@ti.com>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/tile/tilepro.c

@@ -721,9 +721,6 @@ static bool tile_net_poll_aux(struct tile_net_cpu *info, int index)
 	if (!hash_default)
 		__inv_buffer(buf, len);
 
-	/* ISSUE: Is this needed? */
-	dev->last_rx = jiffies;
-
 #ifdef TILE_NET_DUMP_PACKETS
 	dump_packet(buf, len, "rx");
 #endif /* TILE_NET_DUMP_PACKETS */