staging: lustre: libcfs: remove libcfs_ioctl_popdata wrapper

staging: lustre: libcfs: remove libcfs_ioctl_popdata wrapper

Lets just use copy_to_user() directly instead of having a
wrapper function.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: James Simmons <uja.ornl@gmail.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6245
Reviewed-on: http://review.whamcloud.com/14180
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: frank zago <fzago@cray.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>