tools/vm/slabinfo: fix spelling mistake: "Ocurrences" -> "Occurrences"

trivial fix to spelling mistake

Link: http://lkml.kernel.org/r/1466672144-831-1-git-send-email-colin.king@canonical.com


Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>