bpf: Exercise syscall operations for inode and sk storage

bpf: Exercise syscall operations for inode and sk storage

Use the check_syscall_operations added for task_local_storage to
exercise syscall operations for other local storage maps:

* Check the absence of an element for the given fd.
* Create a new element, retrieve and compare its value.
* Delete the element and check again for absence.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-10-kpsingh@chromium.org