new command: BmcBlobWriteMeta

Implement new command BmcBlobWriteMeta.

Change-Id: I2e148f4bde4ef5d24db7e30bb02bdde024d9166a
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/example/example.hpp b/example/example.hpp
index 85f5b17..a85c275 100644
--- a/example/example.hpp
+++ b/example/example.hpp
@@ -58,6 +58,8 @@
                               uint32_t requestedSize) override;
     bool write(uint16_t session, uint32_t offset,
                const std::vector<uint8_t>& data) override;
+    bool writeMeta(uint16_t session, uint32_t offset,
+                   const std::vector<uint8_t>& data) override;
     bool commit(uint16_t session, const std::vector<uint8_t>& data) override;
     bool close(uint16_t session) override;
     bool stat(uint16_t session, struct BlobMeta* meta) override;