Elbert: Reduce VIN LCR Threshold

Summary:
# Description

Currently, the LCR threshold for PSU_VIN sensors on elbert is being exceeded on systems with DC PSU because the input voltage is (as expected) 48V. Updating this threshold to not create false alarms if the DC PSU is inserted.

X-link: facebookexternal/openbmc.arista#391

Test Plan:
Before:
```
root@bmc:~# sensor-util psu1
psu1:
PSU1_VIN                     (0x1) :  48.250 Volts | (lcr)
PSU1_VOUT                    (0x2) :  12.007 Volts | (ok)
PSU1_FAN                     (0x3) : 6184.000 RPM   | (ok)
PSU1_TEMP1                   (0x4) :  33.000 C     | (ok)
PSU1_TEMP2                   (0x5) :  55.000 C     | (ok)
PSU1_TEMP3                   (0x6) :  65.000 C     | (ok)
PSU1_PIN                     (0x7) : 129.500 Watts | (ok)
PSU1_POUT                    (0x8) : 106.000 Watts | (ok)
PSU1_IIN                     (0x9) :   2.679 Amps  | (ok)
PSU1_IOUT                    (0xA) :   8.843 Amps  | (ok)
```

After:
```
root@bmc-oob:~# sensor-util psu1
psu1:
PSU1_VIN                     (0x1) :  48.250 Volts | (ok)
PSU1_VOUT                    (0x2) :  12.007 Volts | (ok)
PSU1_FAN                     (0x3) : 6304.000 RPM   | (ok)
PSU1_TEMP1                   (0x4) :  33.000 C     | (ok)
PSU1_TEMP2                   (0x5) :  54.000 C     | (ok)
PSU1_TEMP3                   (0x6) :  63.000 C     | (ok)
PSU1_PIN                     (0x7) : 131.750 Watts | (ok)
PSU1_POUT                    (0x8) : 107.875 Watts | (ok)
PSU1_IIN                     (0x9) :   2.726 Amps  | (ok)
PSU1_IOUT                    (0xA) :   8.984 Amps  | (ok)
```

Reviewed By: mikechoifb

Differential Revision: D66792905

Pulled By: joancaneus

fbshipit-source-id: 7f737966024ee4721e5f4cd4cda40e65743d9bcd

meta-facebook/meta-elbert/recipes-elbert/platform-lib/files/pal/pal_sensors.c

@@ -3384,7 +3384,7 @@ sensor_thresh_array_init(uint8_t fru) {
     case FRU_PSU4:
       i = fru - FRU_PSU1;
       psu_sensor_threshold[PSU1_VIN + (i * PSU_SENSOR_COUNT)][UCR_THRESH] = 305;
-      psu_sensor_threshold[PSU1_VIN + (i * PSU_SENSOR_COUNT)][LCR_THRESH] = 90;
+      psu_sensor_threshold[PSU1_VIN + (i * PSU_SENSOR_COUNT)][LCR_THRESH] = 35;
       psu_sensor_threshold[PSU1_VIN + (i * PSU_SENSOR_COUNT)][UNC_THRESH] = 0; // unset
       psu_sensor_threshold[PSU1_VIN + (i * PSU_SENSOR_COUNT)][LNC_THRESH] = 0; // unset
       psu_sensor_threshold[PSU1_VOUT + (i * PSU_SENSOR_COUNT)][UCR_THRESH] = 13;