i40e: avoid large memcpy by assigning struct

Assign the i40e_pf structure directly instead of using a large memcpy,
which avoids a sparse warning and lets the compiler optimize the copy
since it knows the size of the structure in advance.

Change-ID: I17604e23be2616521eb760290befcb767b52b3f7
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>