arm64: dts: updates serial aliases for ls1043a rdb and qds boards

-add missing serial aliases to ls1043a-rdb
-update ls1043a-qds boards serial aliases to use the standard duarts
 instead of low power uarts

Signed-off-by: Stuart Yoder <stuart.yoder@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>