max732x: correct nr_port checking off by one error

Setup both client_group_a and client_group_b if nr_port > 8 (not including
nr_port==8).

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Eric Miao <eric.miao@marvell.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>