util: create util object for bmc and tool

Create a common util object for the BMC library and host tool.  Place in
blobs namespace favoring BMC.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I036fd65d924c65fcfa71aba5cd76275a2941ff14
diff --git a/test/firmware_writemeta_unittest.cpp b/test/firmware_writemeta_unittest.cpp
index 4e8cd45..ad7f25b 100644
--- a/test/firmware_writemeta_unittest.cpp
+++ b/test/firmware_writemeta_unittest.cpp
@@ -1,6 +1,7 @@
 #include "data_mock.hpp"
 #include "firmware_handler.hpp"
 #include "image_mock.hpp"
+#include "util.hpp"
 
 #include <sdbusplus/test/sdbus_mock.hpp>
 
@@ -15,7 +16,7 @@
 {
     ImageHandlerMock imageMock1, imageMock2;
     std::vector<HandlerPack> blobs = {
-        {FirmwareBlobHandler::hashBlobID, &imageMock1},
+        {hashBlobId, &imageMock1},
         {"asdf", &imageMock2},
     };
 
@@ -46,7 +47,7 @@
 {
     ImageHandlerMock imageMock1, imageMock2;
     std::vector<HandlerPack> blobs = {
-        {FirmwareBlobHandler::hashBlobID, &imageMock1},
+        {hashBlobId, &imageMock1},
         {"asdf", &imageMock2},
     };