[PATCH] doc: add limitation in using segment-sz in crypto-perf

[Anoob Joseph]

> Subject: [PATCH] doc: add limitation in using segment-sz in crypto-perf
> 
> When segment-sz is given as parameter,
> use buffer-sz in descending order.
> The reason is, same scatter gather buffer list is being used for all packet sizes
> which is initialized once in the beginning.
> Now if a small packet case is run first, mbuf SG list will be trimmed to a smaller
> number of SG and rest of the SGs are lost resulting in segfault.
> Buffers cannot be re-initialized as that will come in datapath and will be costly.
> So to workaround this, if segment-sz is passed as argument, use values in
> buffer-sz in descending order.
> 
> Signed-off-by: Akhil Goyal <gakhil at marvell.com>

Acked-by: Anoob Joseph <anoobj at marvell.com>