Fix benchmark-tests

1. fix all_benchmarks. Some new benchmarks were added.
2. move some benchmark suites to the right place.
3. add unit test for https://android-review.googlesource.com/c/platform/bionic/+/724785

Test: compile and run bionic-benchmarks-tests on device.
Change-Id: I2b686b51910a422b664f9ea968199f37944039c0