sunxi: fix SID read on H3

H3 SID controller has some bug, which makes the initial SID value at
SUNXI_SID_BASE wrong when boot.

Change the SID retrieve code to call the SID Controller directly on H3,
which can get the correct value, and also fix the SID value at
SUNXI_SID_BASE, so that it can be used by further operations.

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>