cleanup: Remove warning for meson build

Removed errors:

```
Found ninja-1.10.1 at /usr/bin/ninja
[3/23] Compiling C++ object libbinarystore.so.p/handler.cpp.o
FAILED: libbinarystore.so.p/handler.cpp.o
c++ -Ilibbinarystore.so.p -I. -I.. -Iproto -I../proto -I/usr/local/include -fdiagnostics-color=always -fsanitize=address,undefined -fno-omit-frame-pointer -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Wnon-virtual-dtor -Wextra -Wpedantic -Werror -std=c++20 -g -fPIC -DBOOST_ASIO_DISABLE_THREADS -DBOOST_ALL_NO_LIB -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_ERROR_CODE_HEADER_ONLY -DBOOST_COROUTINES_NO_DEPRECATION_WARNING -pthread -MD -MQ libbinarystore.so.p/handler.cpp.o -MF libbinarystore.so.p/handler.cpp.o.d -o libbinarystore.so.p/handler.cpp.o -c ../handler.cpp
../handler.cpp: In member function 'virtual bool blobs::BinaryStoreBlobHandler::writeMeta(uint16_t, uint32_t, const std::vector<unsigned char>&)':
../handler.cpp:149:49: error: unused parameter 'session' [-Werror=unused-parameter]
  149 | bool BinaryStoreBlobHandler::writeMeta(uint16_t session, uint32_t offset,
      |                                        ~~~~~~~~~^~~~~~~
../handler.cpp:149:67: error: unused parameter 'offset' [-Werror=unused-parameter]
  149 | bool BinaryStoreBlobHandler::writeMeta(uint16_t session, uint32_t offset,
      |                                                          ~~~~~~~~~^~~~~~
../handler.cpp:150:68: error: unused parameter 'data' [-Werror=unused-parameter]
  150 |                                        const std::vector<uint8_t>& data)
      |                                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
../handler.cpp: In member function 'virtual bool blobs::BinaryStoreBlobHandler::commit(uint16_t, const std::vector<unsigned char>&)':
../handler.cpp:157:65: error: unused parameter 'data' [-Werror=unused-parameter]
  157 |                                     const std::vector<uint8_t>& data)
      |                                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
cc1plus: all warnings being treated as errors
[8/23] Compiling C++ object libbinarystore.so.p/binarystore.cpp.o
FAILED: libbinarystore.so.p/binarystore.cpp.o
c++ -Ilibbinarystore.so.p -I. -I.. -Iproto -I../proto -I/usr/local/include -fdiagnostics-color=always -fsanitize=address,undefined -fno-omit-frame-pointer -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Wnon-virtual-dtor -Wextra -Wpedantic -Werror -std=c++20 -g -fPIC -DBOOST_ASIO_DISABLE_THREADS -DBOOST_ALL_NO_LIB -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_ERROR_CODE_HEADER_ONLY -DBOOST_COROUTINES_NO_DEPRECATION_WARNING -pthread -MD -MQ libbinarystore.so.p/binarystore.cpp.o -MF libbinarystore.so.p/binarystore.cpp.o.d -o libbinarystore.so.p/binarystore.cpp.o -c ../binarystore.cpp
../binarystore.cpp: In static member function 'static std::unique_ptr<binstore::BinaryStoreInterface> binstore::BinaryStore::createFromConfig(const string&, std::unique_ptr<binstore::SysFile>)':
../binarystore.cpp:49:21: error: redundant move in return statement [-Werror=redundant-move]
   49 |     return std::move(store);
      |            ~~~~~~~~~^~~~~~~
../binarystore.cpp:49:21: note: remove 'std::move' call
../binarystore.cpp: In static member function 'static std::unique_ptr<binstore::BinaryStoreInterface> binstore::BinaryStore::createFromFile(std::unique_ptr<binstore::SysFile>, bool)':
../binarystore.cpp:68:21: error: redundant move in return statement [-Werror=redundant-move]
   68 |     return std::move(store);
      |            ~~~~~~~~~^~~~~~~
../binarystore.cpp:68:21: note: remove 'std::move' call
../binarystore.cpp: In member function 'virtual bool binstore::BinaryStore::deleteBlob(const string&)':
../binarystore.cpp:218:49: error: unused parameter 'blobId' [-Werror=unused-parameter]
  218 | bool BinaryStore::deleteBlob(const std::string& blobId)
      |                              ~~~~~~~~~~~~~~~~~~~^~~~~~
cc1plus: all warnings being treated as errors
[13/23] Compiling C++ object test/handler_readwrite_unittest.p/handler_readwrite_unittest.cpp.o
ninja: build stopped: subcommand failed.
```

Change-Id: Id24f2fa9aa4cb4978fa7eb98067e77ee07908248
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/handler.cpp b/handler.cpp
index 66500f4..a391b5a 100644
--- a/handler.cpp
+++ b/handler.cpp
@@ -146,15 +146,15 @@
     return it->second->write(offset, data);
 }
 
-bool BinaryStoreBlobHandler::writeMeta(uint16_t session, uint32_t offset,
-                                       const std::vector<uint8_t>& data)
+bool BinaryStoreBlobHandler::writeMeta(uint16_t, uint32_t,
+                                       const std::vector<uint8_t>&)
 {
     /* Binary store handler doesn't support write meta */
     return false;
 }
 
 bool BinaryStoreBlobHandler::commit(uint16_t session,
-                                    const std::vector<uint8_t>& data)
+                                    const std::vector<uint8_t>&)
 {
     auto it = sessions_.find(session);
     if (it == sessions_.end())