Fix unit issue in policy feature (#78)

1. For temperature the unit in milli Celsius
2. For power the unit in microwatts.
3. Fix second register call to rdcd doesn't functional because start flag

Co-authored-by: Chao Fei <chao.fei@amd.com>

include/rdc/rdc.h

@@ -593,7 +593,7 @@ typedef enum {
   RDC_POLICY_COND_FIRST = 0,
   RDC_POLICY_COND_MAX_PAGE_RETRIED = RDC_POLICY_COND_FIRST,  //!< Max number of page retired
   RDC_POLICY_COND_THERMAL,  //!< Temperature threshold, millidegree Celsius
-  RDC_POLICY_COND_POWER,    //!< Power threshold, unit milliwatt
+  RDC_POLICY_COND_POWER,    //!< Power threshold, unit microwatt
   RDC_POLICY_COND_LAST = RDC_POLICY_COND_POWER,
   RDC_POLICY_COND_MAX
 } rdc_policy_condition_type_t;