module: deprecate usage of *_gpl sections in module loader

module: deprecate usage of *_gpl sections in module loader

The *_gpl section are not being used populated by modpost anymore. Hence
the module loader doesn't need to find and process these sections in
modules.

This patch also simplifies symbol finding logic in module loader since
*_gpl sections don't have to be searched anymore.

Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>