Run test with single source input and output files

This commit allows us to run a test when it requires only
a single source and expected output file.
Use do_run_from_file() for test_hello_world
Use do_run_from_file() for test_intvars
Use do_run_from_file() for test_sintvars
Use do_run_from_file() for test_i64_b
Use do_run_from_file() for test_i64_cmp
Use do_run_from_file() for test_i64_cmp2
Use do_run_from_file() for test_i64_double
Use do_run_from_file() for test_i64_umul
Use do_run_from_file() for test_i64_llabs
Use do_run_from_file() for test_i64_zextneg
Use do_run_from_file() for test_i64_7z
Use do_run_from_file() for test_i64_i16
Use do_run_from_file() for test_i64_qdouble
Use do_run_from_file() for test_i64_varargs
Use do_run_from_file() for test_i32_mul_precise
Use do_run_from_file() for test_i32_mul_semiprecise
Use do_run_from_file() for test_i16_emcc_intrinsic
Use do_run_from_file() for test_double_i64_conversion
Use do_run_from_file() for test_float32_precise