mtd: onenand: fix deadlock in onenand_block_markbad

Commit 5942ddbc ("mtd: introduce mtd_block_markbad interface")
incorrectly changed onenand_block_markbad() to call mtd_block_markbad
instead of onenand_chip's block_markbad function. As a result the function
will now recurse and deadlock. Fix by reverting the change.

Fixes: 5942ddbc ("mtd: introduce mtd_block_markbad interface")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>