scripts: west_commands: runners: Update GDB args

Update gdb arguments to enable linkserver
debugging when app does not reset after load.
This is useful for when the app is loading to
ram. In this case if gdb reset after loaded the
ram would be flushed when debugging and there would be
nothing no image in ram to debug.

Signed-off-by: Emilio Benavente <emilio.benavente@nxp.com>