Using code like:

    int foo , bar;

is not preferred to:

    int foo, bar;

so emit an error on this style.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>