Revert "net: preserve IP control block during GSO segmentation"

Revert "net: preserve IP control block during GSO segmentation"

Orabug: 23522263

This reverts commit a9e889c735eef731df3fce53fb997277f3b0b498.

Yuval Shaia and team discovered that the aforementioned commit
resulted in a substantial (900-to-1) performance loss on a TCP
bandwidth test over IPoIB.  Upstream is aware of the problem
but there is currently no solution in hand, so just revert the
offending commmit.

Note that the original commit purports to fix a kernel crash,
but so far we haven't seen the crash.

Signed-off-by: Dan Duval <dan.duval@oracle.com>
Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Tested-by: Rose Wang <rose.wang@oracle.com>