ixgbe: Remove IXGBE_FLAG_IN_NETPOLL since it doesn't do anything

This patch removes some dead code from the cleanup path for ixgbe.

Setting and clearing the flag doesn't do anything since all we are
doing is setting the flag, scheduling NAPI, clearing the flag and
then letting netpoll do the polling cleanup.  As such it doesn't
make much sense to have it there.

This patch also removes one minor white-space error.

CC: <kernel-team@fb.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>