i40e: don't check params until after checking for client instance

We can avoid the minor bit of work by calling check params after we
check for the client instance, since we're about to return early in
cases where we do not have a client.

Change-ID: I56f8ea2ba48d4f571fa331c9ace50819a022fa1c
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>