power_management: add TCID

get_sched_values.c uses interfaces provided by -lltp which need
TCID defined. Not sure how this built successfully before.

[v2] correct TCID to an unique one

Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>