PEL: Updated PEL spec error action flag bit#10

- This will help to indicate which SRCs need to be collected and
regularly called home.
- Defined new entry in message registry schema action flags field
- Set this action flag in the registry for the daily clock PEL
and the voltage regulator N+1 phase fault PEL

Tested:
Sample output:
```bash
$ peltool -af
...
    "Action Flags": [
                                "Report Externally",
                                "Heartbeat Call Home Event"
...
    "Action Flags": [
                                "Report Externally",
                                "HMC Call Home",
                                "Heartbeat Call Home Event"
...
$ peltool -afx
...
00000030  55 48 00 18 01 00 20 00  60 03 00 01 00 00 00 00  |
00000040  00 00 20 20 00 00 00 00  50 53 00 50 01 01 27 00  |
...
00000030  55 48 00 18 01 00 20 00  58 03 00 01 00 00 00 00  |
00000040  00 00 28 20 00 00 00 00  50 53 00 50 01 01 30 00  |
...

```
Change-Id: Ifa181374692013dfadc0dd744f6db61baad3d42e
Signed-off-by: Harsh Agarwal <Harsh.Agarwal@ibm.com>
diff --git a/extensions/openpower-pels/pel_values.cpp b/extensions/openpower-pels/pel_values.cpp
index a94606c..d584c3a 100644
--- a/extensions/openpower-pels/pel_values.cpp
+++ b/extensions/openpower-pels/pel_values.cpp
@@ -199,7 +199,8 @@
     {0x0800, "call_home", "HMC Call Home"},
     {0x0400, "isolation_incomplete",
      "Isolation Incomplete, further analysis required"},
-    {0x0100, "termination", "Service Processor Call Home Required"}};
+    {0x0100, "termination", "Service Processor Call Home Required"},
+    {0x0020, "heartbeat_call_home", "Heartbeat Call Home Event"}};
 
 /**
  * The possible values for the Callout Priority field in the SRC.