drivers/net: Remove unnecessary returns from void function()s

This patch removes from drivers/net/ all the unnecessary
return; statements that precede the last closing brace of
void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

It also does not remove null void functions with return.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
  xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'

with some cleanups by hand.

Compile tested x86 allmodconfig only.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/octeon/octeon_mgmt.c

@@ -1005,7 +1005,6 @@ static void octeon_mgmt_poll_controller(struct net_device *netdev)
 
 	octeon_mgmt_receive_packets(p, 16);
 	octeon_mgmt_update_rx_stats(netdev);
-	return;
 }
 #endif