The TI816x has 2 GPIO banks. For bank 0 we had been clearing the enable
bit when setting BIT(8). Correct this by setting it to BIT(1) | BIT(8)
after we set and wait for BIT(1) (aka PRCM_MOD_EN). Enable GPIO1 as
well so that when CMD_GPIO is enabled it won't crash probing the second
bank. Enable CMD_GPIO on ti816x_evm.
Signed-off-by: Tom Rini <trini@konsulko.com>