avr32: off by one in at32_init_pio()

commit 55f1cf83d5cf885c75267269729805852039c834 upstream.

The pio_dev[] array has MAX_NR_PIO_DEVICES elements so the > should be
>=.

Fixes: 5f97f7f9 ('[PATCH] avr32 architecture')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>