fby3: dl: support OEM get reading command for ME (#513)

Summary:
- Since the HSC has multiple sources, the ME will get power readings from the bic.

Pull Request resolved: #513

Test Plan:
1. Build code : pass

2. IPMI oem command:
root@bmc-oob:~# bic-util slot2 0xc0 0xe2 0x0 0x0 0x0
00 17 00

3. Check the power reading from me:
root@bmc-oob:~# me-util slot2 0xb8 0xc8 0x57 0x01 0x00 0x1 0x0 0x0
57 01 00 18 00 17 00 21 00 18 00 FF FF FF FF EF 2E 00 00 50

Reviewed By: garnermic

Differential Revision: D38989044

Pulled By: GoldenBug

fbshipit-source-id: 9ee622ba0e0658fc123d92537590acf18861bfad

meta-facebook/yv3-dl/src/platform/plat_sensor_table.c

@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <logging/log.h>
 #include "plat_sensor_table.h"
 #include "sensor.h"
 #include "ast_adc.h"
@@ -16,6 +17,8 @@
 #include "libutil.h"
 #include "util_sys.h"
 
+LOG_MODULE_DECLARE(sensor);
+
 struct k_mutex vr_page_mutex;
 
 sensor_cfg plat_sensor_config[] = {
@@ -366,3 +369,9 @@ void pal_extend_sensor_config()
 
 	return;
 }
+
+uint8_t get_hsc_pwr_reading(int *reading)
+{
+	CHECK_NULL_ARG_WITH_RETURN(reading, SENSOR_UNSPECIFIED_ERROR);
+	return get_sensor_reading(SENSOR_NUM_HSC_PIN, reading, GET_FROM_CACHE);
+}