net/iavf: fix Rx function selection

net/iavf: fix Rx function selection

A performance drop is caused by that the RX scalar path
is selected when AVX512 is disabled and some HW offload
is enabled.
Actually, the HW offload is supported by AVX2 and SSE.
In this scenario AVX2 path should be chosen.

This patch removes the offload related check for SSE and AVX2
as SSE and AVX2 do support the offload features.
No implementation change about the data path.

Fixes: eff56a7b9f97 ("net/iavf: add offload path for Rx AVX512")

Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>