net/mlx5: fix build with clang on ARM

net/mlx5: fix build with clang on ARM

This patch adds a pair of "()" to embrace the argument
input to the function-like macro invocation.

drivers/net/mlx5/mlx5_rxtx_vec.c:37:
drivers/net/mlx5/mlx5_rxtx_vec_neon.h:170:24: error: too many arguments
provided to function-like macro invocation
	(uint16x8_t) { 0, 0, cs_flags, rte_cpu_to_be_16(len),

Fixes: 570acdb1da ("net/mlx5: add vectorized Rx/Tx burst for ARM")
Cc: stable@dpdk.org
Signed-off-by: Gavin Hu <gavin.hu@arm.com>
Signed-off-by: Sirshak Das <sirshak.das@arm.com>
Reviewed-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Yongseok Koh <yskoh@mellanox.com>