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/wireless/rt2x00/rt2x00debug.c

@@ -700,8 +700,6 @@ void rt2x00debug_register(struct rt2x00_dev *rt2x00dev)
 exit:
 	rt2x00debug_deregister(rt2x00dev);
 	ERROR(rt2x00dev, "Failed to register debug handler.\n");
-
-	return;
 }
 
 void rt2x00debug_deregister(struct rt2x00_dev *rt2x00dev)