Rewordings required in logging PEL

This commit rewords some of the comments and variables
in restore VPD PEL code and in vpd-tool restore function.

Eg:
>>Cache value -> Backup value
    [As backup need not be in cache only]
>>Blank data -> Default data
    [As default data need not be blank only]
>>Hardware data -> Primary data
The VPD backup values and backup memory are machine specific.

Thus providing generic terms makes the code statements/comments
more reliable w.r.t any machine.

Signed-off-by: Priyanga Ramasamy <priyanga24@in.ibm.com>
Change-Id: I34fcd44e94b928db0fc30cda94eb8f03e6e87987
diff --git a/vpd_tool_impl.hpp b/vpd_tool_impl.hpp
index 4a75a71..669232a 100644
--- a/vpd_tool_impl.hpp
+++ b/vpd_tool_impl.hpp
@@ -151,10 +151,10 @@
     enum UserOption
     {
         EXIT = 0,
-        BMC_DATA_FOR_ALL = 1,
+        BACKUP_DATA_FOR_ALL = 1,
         SYSTEM_BACKPLANE_DATA_FOR_ALL = 2,
         MORE_OPTIONS = 3,
-        BMC_DATA_FOR_CURRENT = 4,
+        BACKUP_DATA_FOR_CURRENT = 4,
         SYSTEM_BACKPLANE_DATA_FOR_CURRENT = 5,
         NEW_VALUE_ON_BOTH = 6,
         SKIP_CURRENT = 7