rockchip: dts: fix bootph tags for rv1126

RV1126 fails to boot on 2024.01-rc1.

Commit 9e644284 ("dm: core: Report bootph-pre-ram/sram node as
pre-reloc after relocation") changed the behaviour of bootph-pre-ram, to
limit nodes to spl phase. This caused rv1126 boards to fail to boot with
the current dts.

This patch updates the pmu/grf nodes to bootph-all tags as they are
needed in all phases. This fixes the boot issue on rv1126 boards.

Signed-off-by: Tim Lunn <tim@feathertop.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>