dbus-sensors: utils: Utility to get device bus & addr from dev name.

This is applicable to all the services which rely on "bus-addr" fmt.
1. FanSensor
2. HwmonTempSensor
3. IntelCPUSensor
4. PSUSensor

In addition this would also fix Fansensor Daemon crashes due to
stoi() exceptions weren't caught earlier.

For example: In a FanSensor Daemon -
Device of f0103000.pwm-fan-controller would be classified as i2cfan
based on new way of defining fan type.
Hence when we parse string for bus-addr, bus=f0103000.pwm and
addr=fan-controller for which stoi() would crash.
This would be true for all non I2c devices defaulting to I2cFan type.

Solution is to use 'std::from_chars' which handles under/overflow
properly. Centralizing this now in Utils would also allow us to manage
this appropriatelty across various services.

Tested:
Tested sanity of all daemons in the system and they work as expected.

Change-Id: I546e967abae7c0fb9fca645867e3037046037647
Signed-off-by: Akshit Shah <shahakshit@google.com>
diff --git a/src/IntelCPUSensorMain.cpp b/src/IntelCPUSensorMain.cpp
index ba36e41..005ed7e 100644
--- a/src/IntelCPUSensorMain.cpp
+++ b/src/IntelCPUSensorMain.cpp
@@ -195,23 +195,10 @@
         fs::path::iterator it = hwmonNamePath.begin();
         std::advance(it, 6); // pick the 6th part for a PECI client device name
         std::string deviceName = *it;
-        auto findHyphen = deviceName.find('-');
-        if (findHyphen == std::string::npos)
-        {
-            std::cerr << "found bad device " << deviceName << "\n";
-            continue;
-        }
-        std::string busStr = deviceName.substr(0, findHyphen);
-        std::string addrStr = deviceName.substr(findHyphen + 1);
 
         size_t bus = 0;
         size_t addr = 0;
-        try
-        {
-            bus = std::stoi(busStr);
-            addr = std::stoi(addrStr, nullptr, 16);
-        }
-        catch (const std::invalid_argument&)
+        if (!getDeviceBusAddr(deviceName, bus, addr))
         {
             continue;
         }