Staging: sxg: Add NAPI feature to Sahara SXG Driver

* Add NAPI support for SXG driver for Alacritech's 10Gbe products.
  The driver will now work in NAPI mode by default.

Signed-off-by: LinSysSoft Sahara Team <saharaproj@linsyssoft.com>
Signed-off-by: Mithlesh Thukral <mithlesh@linsyssoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>