bmc: add utilty method to only add a blob id if not present

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I96f3335a1341bc29eeff398f200214f240861047
diff --git a/firmware_handler.hpp b/firmware_handler.hpp
index def20a8..3f2d21d 100644
--- a/firmware_handler.hpp
+++ b/firmware_handler.hpp
@@ -8,6 +8,7 @@
 #include "util.hpp"
 #include "verify.hpp"
 
+#include <algorithm>
 #include <blobs-ipmid/blobs.hpp>
 #include <cstdint>
 #include <map>
@@ -176,6 +177,17 @@
     };
 
   private:
+    void addBlobId(const std::string& blob)
+    {
+        auto blobIdMatch =
+            std::find_if(blobIDs.begin(), blobIDs.end(),
+                         [&blob](const auto& iter) { return (iter == blob); });
+        if (blobIdMatch == blobIDs.end())
+        {
+            blobIDs.push_back(blob);
+        }
+    }
+
     /** List of handlers by type. */
     std::vector<HandlerPack> handlers;