UEAGLE: fix ueagle-atm Oops

The array of attribute passed to sysfs_create_group() must be
NULL-terminated.

The sysfs entries are created before the start of the modem state machine
to avoid to stop it in case of errors in sysfs creation.  Also
{destroy,create}_fs_entries are removed as they do nothing.

Signed-off-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>