log consistently via stderr

Most log messages in this codebase use stderr, while a few used
phosphor-logging.  Transition all to use stderr.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: Ic4cf619950275a2752f646f00974047092757010
diff --git a/cleanup/main.cpp b/cleanup/main.cpp
index 09bdb72..91e7297 100644
--- a/cleanup/main.cpp
+++ b/cleanup/main.cpp
@@ -35,14 +35,12 @@
 
 extern "C" std::unique_ptr<blobs::GenericBlobInterface> createHandler()
 {
-    using namespace phosphor::logging;
-
     auto handler = ipmi_flash::FileCleanupHandler::CreateCleanupHandler(
         ipmi_flash::cleanupBlobId, ipmi_flash::files);
 
     if (!handler)
     {
-        log<level::ERR>("Unable to create FileCleanupHandle for Firmware");
+        std::fprintf(stderr, "Unable to create FileCleanupHandle for Firmware");
         return nullptr;
     }