samples: tracing: run openocd sample with 1 cpu

openocd thread awareness support does not work with multiple CPUs
enabled.

Signed-off-by: Anas Nashif <[email protected]>

Author: nashif

samples/subsys/tracing/sample.yaml

@@ -20,6 +20,7 @@ tests:
       - CONFIG_TRACING_CPU_STATS=y
   tracing.backends.openocd:
     extra_configs:
+      - CONFIG_MP_NUM_CPUS=1
       - CONFIG_OPENOCD_SUPPORT=y
       - CONFIG_SMP=n
     arch_exclude: posix xtensa