PLDM: Implementing Phosphor-Logging/LG2 logging

This commit migrates std::cerr/cout added as part
of new changes in PLDM to LG2.

Change-Id: I8e85732684d47b6740521e95712433a7c6760d8a
Signed-off-by: Riya Dixit <riyadixitagra@gmail.com>
diff --git a/pldmd/pldmd.cpp b/pldmd/pldmd.cpp
index 11c4ec2..b8315b7 100644
--- a/pldmd/pldmd.cpp
+++ b/pldmd/pldmd.cpp
@@ -148,9 +148,9 @@
 
 void optionUsage(void)
 {
-    error("Usage: pldmd [options]");
-    error("Options:");
-    error(" [--verbose] - would enable verbosity");
+    info("Usage: pldmd [options]");
+    info("Options:");
+    info(" [--verbose] - would enable verbosity");
 }
 
 int main(int argc, char** argv)