arm64: dts: allwinner: a64: Fix a typo

This typo inverted the meaning of the comment, but the rest of the
comment and the code reveal that the regulator in question needs to be
on at all times.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>