TPM code updater

This commit introduces a TPM code updater that currently supports
reading the firmware version for both Infineon and Nuvoton TPM 2.0.
Support for firmware updates will be introduced in a future patch.

The updater's configuration are managed by the EM [1].
[1] https://gerrit.openbmc.org/c/openbmc/entity-manager/+/82416

Tested on Yosemite5 with the following steps:

1. Display the fw inventory:
```
curl --silent $creds https://$bmc/redfish/v1/UpdateService/FirmwareInventory
{
  "@odata.id": "/redfish/v1/UpdateService/FirmwareInventory",
  "@odata.type": "#SoftwareInventoryCollection.SoftwareInventoryCollection",
  "Members": [
    {...},
    {
      "@odata.id": "/redfish/v1/UpdateService/FirmwareInventory/Yosemite5_TPM_4945"
    },
    {...}
  ],
  "Members@odata.count": 4,
  "Name": "Software Inventory Collection"
}
```

2. Query TPM version:
```
curl --silent $creds https://$bmc/redfish/v1/UpdateService/FirmwareInventory/Yosemite5_TPM_4945
{
  "@odata.id": "/redfish/v1/UpdateService/FirmwareInventory/Yosemite5_TPM_4945",
  "@odata.type": "#SoftwareInventory.v1_1_0.SoftwareInventory",
  "Description": "Unknown image",
  "Id": "Yosemite5_TPM_4945",
  "Name": "Software Inventory",
  "Status": {
    "Health": "Warning",
    "HealthRollup": "OK",
    "State": "Disabled"
  },
  "Updateable": false,
  "Version": "15.23"
}
```

Change-Id: I42568242356d55fe005ba1f41ddf8aaf9f682fc8
Signed-off-by: Kevin Tung <kevin.tung.openbmc@gmail.com>
diff --git a/common/include/utils.hpp b/common/include/utils.hpp
index 928b136..65d7022 100644
--- a/common/include/utils.hpp
+++ b/common/include/utils.hpp
@@ -2,11 +2,15 @@
 
 #include <sdbusplus/async.hpp>
 
+#include <functional>
+#include <optional>
+
 /**
  * @brief Asynchronously executes a shell command.
  * @param ctx Async context for monitoring the pipe.
  * @param cmd Shell command to execute.
  * @return Task resolving to true on success (exit code 0), false otherwise.
  */
-sdbusplus::async::task<bool> asyncSystem(sdbusplus::async::context& ctx,
-                                         const std::string& cmd);
+sdbusplus::async::task<bool> asyncSystem(
+    sdbusplus::async::context& ctx, const std::string& cmd,
+    std::optional<std::reference_wrapper<std::string>> result = std::nullopt);