revert "ipv4: Should use consistent conditional judgement for ip fragment in __ip_append_data and ip_finish_output"

This reverts commit f102bb71 which is
commit 0a28cfd5 upstream as there is
another patch that needs to be applied instead of this one.

Cc: Zheng Li <james.z.li@ericsson.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>