The common PnP serial port DSDT code is intentionally included twice for two serial ports with different LDNs. Undefine LDN and the PM register name before redefining for second serial port so iasl doesn't complain. Change-Id: I031905479c66698fb01da028e3f37d923396d2d9 Signed-off-by: Keith Hui <buurin@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/41095 Reviewed-by: Patrick Georgi <pgeorgi@google.com> Reviewed-by: Angel Pons <th3fanbus@gmail.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>