fm10k: Fix misuse of net_ratelimit()

Correct the backward logic using !net_ratelimit()

Miscellanea:

o Add a blank line before the error return label

Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>