octeontx2-pf: Do not use HW TSO when gso_size < 16bytes

commit f481e1a4979b479cdf301e6c0bb1b97c9c2e1224 from
git@git.assembla.com:cavium/WindRiver.linux.git

Hardware doesn't support packet segmentation when segment size
is <16 bytes. Hence add an additional check and use SW
segmentation in such case.

Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Change-Id: I011815d03811381a2073b3339865042125c5c62f
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/123130


Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>