selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch

selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch

In order to do the following load-acquire and store-release tests on
LoongArch:

  sudo ./test_progs -t verifier_load_acquire
  sudo ./test_progs -t verifier_store_release
  sudo ./test_progs -t verifier_precision/bpf_load_acquire
  sudo ./test_progs -t verifier_precision/bpf_store_release
  sudo ./test_progs -t compute_live_registers/atomic_load_acq_store_rel

It needs to enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>