staging: lustre: add a blank line after function/struct/union/enum declarations

Fixes checkpatch.pl CHECK:LINE_SPACING: Please use a blank line after
function/struct/union/enum declarations

The patch is generated using checkpatch.pl --fix-inplace:

for f in $(find drivers/staging/lustre/ -type f) ; do
    ./scripts/checkpatch.pl --types "LINE_SPACING" --fix-inplace -f $f
done

Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>