Support multiple sensors of same fru_type/label

There are some DDR5 DIMMs that have multiple DRAM temperature sensors,
of which we only care about the hotter one.

As the OCC reports these with the same fru_type and label values, the
code will need to read them both, and then just put the maximum value on
D-Bus.

Support this generically by first looping through all of the sysfs files
and saving the temperature values along with the calculated D-Bus object
path, handling the multiple sensor case by only storing the maximum
value, and then looping through the saved values and putting them on
D-Bus.

Tested:
Found sensors 33 and 34 are the same fru type and label:

temp33_fru_type:2
temp33_label:3489726464
temp33_input:38000

temp34_fru_type:2
temp34_label:3489726464
temp34_input:39000

Before change, the cooler one was on D-Bus:
```
d 38
```

After change, the hotter one was:

```
temp33_input:39000
temp34_input:41000

d 41
```

Change-Id: Ida632b9784209079d9d1bfc6c21918cd65be6a1f
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
1 file changed