e1000e: Use kmemdup rather than duplicating its implementation

The semantic patch that makes this output is available
in scripts/coccinelle/api/memdup.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/



Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by:  <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>