regulator: lp8788-ldo: Remove val array in lp8788_config_ldo_enable_mode

To clear the mask bit, setting data argument to be 0 with proper mask setting
for lp8788_update_bits. We don't need the var array here.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>