tools: remove phosphor-ipmi-blobs dependency

The host tool depended on the BMC header: firmware_handler.hpp because
it defined the flags.  This header depends on phosphor-ipmi-blobs,
therefore the host-tool depends on this.  Move the flags into a separate
common header file and snip this dependency.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: Id2ad33a1611c02605a1ed5c695429d0451eb98d4
diff --git a/tools/interface.hpp b/tools/interface.hpp
index ae341ec..2c993bf 100644
--- a/tools/interface.hpp
+++ b/tools/interface.hpp
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "firmware_handler.hpp"
+#include "flags.hpp"
 
 #include <cstdint>
 #include <string>
@@ -30,8 +30,7 @@
      *
      * @return the enum value corresponding to the supported type.
      */
-    virtual ipmi_flash::FirmwareBlobHandler::UpdateFlags
-        supportedType() const = 0;
+    virtual ipmi_flash::FirmwareFlags::UpdateFlags supportedType() const = 0;
 };
 
 } // namespace host_tool