ixgbevf: Return error on failure to enable VLAN

ixgbevf: Return error on failure to enable VLAN

With recent kernel changes we can now return errors on a failure to setup a
VLAN filter.  This patch takes advantage of that opportunity so that we can
return either an EIO error in the case of a mailbox failure, or an EACCESS
error in the case of being denied access to the VLAN filter table by the
PF.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Robert Garrett <robertx.e.garrett@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>