ARM: dts: sun7i: Fix pll3x2 and pll7x2 not having a parent clock

Fix pll3x2 and pll7x2 not having a parent clock, specifically this
fixes the kernel turning of pll3 while simplefb is using it when
uboot has configured things to use pll3x2 as lcd ch clk parent.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>