plugin_test.py: Remove test_close

This isn't needed as the tear down is exercising close.  With this test
we hang when running against the simulator as we are trying to access the
state file which is already open.

Signed-off-by: Tony Asleson <tasleson@redhat.com>
Signed-off-by: Gris Ge <fge@redhat.com>
plugin_test.py: Call fs_child_dependency_rm regardless

In the case where it really isn't necessary we will check for a None
response which is expected in this case.

V2: Fix call arguments, doh!

Signed-off-by: Tony Asleson <tasleson@redhat.com>
Signed-off-by: Gris Ge <fge@redhat.com>
C API: Fix simc plugin and correct plugin header doxygen parameters

Plugin IPC for C plugins wasn't allowing some of the parameters to be NULL,
which they can be according to the header documentation.  Fixed up code to
accomodate this valie use case.  Also fixed a bug in ss_restore, we were
checking v_files twice instead of v_files and v_restore_file.

Signed-off-by: Tony Asleson <tasleson@redhat.com>
Signed-off-by: Gris Ge <fge@redhat.com>