LU-9859 libcfs: remove cfs_capable

LU-9859 libcfs: remove cfs_capable

Use capable() directly.

Linux-commit: 2eb90a757e9d953c9e2a8fce530422189992fb1b

Change-Id: Iadaa3c743a350def37558b23d954f5dfd4e0844a
Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-on: https://review.whamcloud.com/41783
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Reviewed-by: Oleg Drokin <green@whamcloud.com>