[WAN]: kfree of NULL pointer is valid

kfree(0) is perfectly valid, checking pointers for NULL before calling 
kfree() on them is redundant. The patch below cleans away a few such 
redundant checks (and while I was around some of those bits I couldn't 
stop myself from making a few tiny whitespace changes as well).

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Acked-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>