Remove unused variables in MemStore.cc

Removes two unused variables expected_object_size and
expected_write_size in MemStore.cc

Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@cloudwatt.com>
Remove unused variables in KeyValueStore.cc

Removes two unused variables expected_object_size and
expected_write_size in KeyValueStore.cc

Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@cloudwatt.com>
Merge pull request #1916 from sahid/unused

Remove unused variables on MemStore.cc and KeyValueStore.cc

Reviewed-by: Loic Dachary <loic@dachary.org>