Add little-endian property to RCPM node (for ls1028a,ls1088a,ls208xa),
otherwise RCPM driver will program hardware with incorrect setting,
causing system (such as LS1028ARDB) failed to be waked by wakeup source.

Fixes: 791c88ca (“arm64: dts: ls1028a: Add ftm_alarm0 DT node”)
Fixes: f4fe3a86 (“arm64: dts: layerscape: add ftm_alarm0 node”)
Signed-off-by: Biwen Li <biwen.li@nxp.com>
Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>