net/hns3: fix vector Rx burst limitation

net/hns3: fix vector Rx burst limitation

Currently, driver uses the macro HNS3_DEFAULT_RX_BURST whose value is
32 to limit the vector Rx burst size, as a result, the burst size
can't exceed 32.

This patch fixes this problem by support big burst size.
Also adjust HNS3_DEFAULT_RX_BURST to 64 as it performs better than 32.

Fixes: a3d4f4d291d7 ("net/hns3: support NEON Rx")
Fixes: 952ebacce4f2 ("net/hns3: support SVE Rx")
Cc: stable@dpdk.org
Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>