net/bnxt: fix aarch32 build

net/bnxt: fix aarch32 build

NEON vector path of the PMD needs aarch64 support. But it was
enabled for aarch32 build as well because aarch32 build had
cpu_family set to aarch64. So build for aarch32 will fail due
to unsupported intrinsics.

Fix aarch32 build by updating meson file to exclude NEON vector
implementation for aarch32.

Fixes: 398358341419 ("net/bnxt: support NEON")
Cc: stable@dpdk.org
Signed-off-by: Ruifeng Wang <ruifeng.wang@arm.com>
Reviewed-by: Lance Richardson <lance.richardson@broadcom.com>