i40e/i40evf: Change type to u32 to avoid sparse error

tx_lpi_status and rx_lpi_status are declared as bool but then used in sizeof
operations in the CORE driver code.  Make them u32 to make sparse be quiet.

Change-ID: Iad6daeb1c7149e61ece242acd18c64b320c246a3
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Jim Young <jamesx.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>