romio: port tests to mpich test suite

[hzhou]

The tests in src/mpi/romio/test are partially ported to test/mpi/io. We should port all ROMIO tests to test/mpi/io and then remove src/mpi/romio/test. Since MPICH testsuite are distributed separately, it can serve the use cases where ROMIO is built outside MPICH.

Reference: issue #3957 #4670

The first step is to identify a list of tests under src/mpi/romio/test that are not covered by test/mpi/io.

[hzhou]

1. Identify a list of tests that are already ported to test/mpi/io
2. Identify a list of tests in romio/test that need to be ported
3. Remove the tests in romio/test that has already been ported