arm: dts: ipq5424-rdp466: add chosen node for serial console

Add a /chosen node with stdout-path pointing to serial0 (uart1) to
enable the DT-driven console discovery path in
serial_find_console_or_panic().

Without this node, the live DT path in serial_find_console_or_panic()
is skipped and the fallback path is used. Adding the /chosen node makes
the console selection explicit and deterministic, ensuring the correct
serial device is always selected as the console.

Signed-off-by: Gurumoorthy Santhakumar <gurumoorthy.santhakumar@oss.qualcomm.com>
Link: https://patch.msgid.link/20260603113853.3396271-1-gurumoorthy.santhakumar@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>