Created by: DannyIsFunny

[Issue] CI task PR_CI_Paddle-Lite-server may fail occasionally on the unit test sgemm_test [Reason] #4201 has increased the time consumed by sgemm_test, sgemm_test may break abnomally for timeout. [Effect of Current PR] Reduce sgemm_test time on x86 backend, while sgemm_test will remain its previous performance on arm backend.