i40e/i40evf: fix rx descriptor status

As reported by Eric Dumazet, the driver is not masking the right
bits in the receive descriptor before it starts checking them.

This patch extends the mask to allow for the right bits to be
checked, and fixes the issue permanently via a define.

CC: Eric Dumazet <eric.dumazet@gmail.com>
Change-ID: I3274f7619057a950f468143e6d7e11b129f54655
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>