power: axp818: Fix typo in axp_set_dldo

Fix typo in axp_set_dldo() so that it correctly uses AXP818_DLDO1_CTRL
register to configure the voltage instead of setting AXP818_ELDO1_CTRL
register which is obviously incorrect.

Signed-off-by: Ondřej Jirman <megous@megous.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>