PEL: Use raw procedure names in PEL msg reg

Start using the raw maintenance procedure names in the PEL message
registry, such as BMC0001, instead of the enum values, such as
'bmc_firmware'.  This way, the script that generates documentation can
list the procedure in the section for that PEL.  This was requested by
the support team.

Note that there is still one user of the enums - the checkstop analysis
code uses them when it creates callouts by passing in them via JSON user
data files.

There are pointers added to the README and schema to find the available
procedures and their descriptions.

Tested:
- The unit tests still work which verify the callout contents when PEL
  callouts are created via the message registry.
- Also manually verified PEL procedure callouts look correct when
  created from the message registry.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I3e8416956120d4dae1ff40592fd0df4f0285d072
diff --git a/test/openpower-pels/registry_test.cpp b/test/openpower-pels/registry_test.cpp
index 2f715bb..1fb78b0 100644
--- a/test/openpower-pels/registry_test.cpp
+++ b/test/openpower-pels/registry_test.cpp
@@ -458,7 +458,7 @@
             [
                 {
                     "Priority": "medium",
-                    "Procedure": "bmc_code"
+                    "Procedure": "BMC0001"
                 },
                 {
                     "Priority": "low",
@@ -503,7 +503,7 @@
         EXPECT_EQ(callouts.size(), 2);
         EXPECT_EQ(callouts[0].priority, "medium");
         EXPECT_EQ(callouts[0].locCode, "");
-        EXPECT_EQ(callouts[0].procedure, "bmc_code");
+        EXPECT_EQ(callouts[0].procedure, "BMC0001");
         EXPECT_EQ(callouts[0].symbolicFRU, "");
         EXPECT_EQ(callouts[1].priority, "low");
         EXPECT_EQ(callouts[1].locCode, "P3-C8");
@@ -616,7 +616,7 @@
                                 },
                                 {
                                     "Priority": "low",
-                                    "Procedure": "bmc_code",
+                                    "Procedure": "BMC0001",
                                     "CalloutType": "config_procedure"
                                 }
                             ]
@@ -671,7 +671,7 @@
             EXPECT_EQ(callouts[1].symbolicFRUTrusted, "");
             EXPECT_EQ(callouts[2].priority, "low");
             EXPECT_EQ(callouts[2].locCode, "");
-            EXPECT_EQ(callouts[2].procedure, "bmc_code");
+            EXPECT_EQ(callouts[2].procedure, "BMC0001");
             EXPECT_EQ(callouts[2].symbolicFRU, "");
             EXPECT_EQ(callouts[2].symbolicFRUTrusted, "");