docs: symbol-namespaces: mention sysfs attribute
Reference the new /sys/module/*/import_ns sysfs attribute in docs as an
alternative to modinfo for inspecting imported namespaces of loaded
modules.
Signed-off-by: Nicholas Sielicki <linux@opensource.nslick.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
authored by