This patch adds an inverted "jumbo ring enable" test and jumps to the exit
if it succeeds.  The change reduces the indent level of the remaining
code making it more readable.
Signed-off-by: NMatt Carlson <mcarlson@broadcom.com>
Reviewed-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>