ceph_objectstore_test: fix warnings

ceph_objectstore_test: fix warnings

In file included from test/objectstore/store_test.cc:34:0:
../src/gmock/gtest/include/gtest/gtest.h: In instantiation of ‘testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = unsigned int; T2 = int]’:
../src/gmock/gtest/include/gtest/gtest.h:1484:23:   required from ‘static testing::AssertionResult testing::internal::EqHelper<lhs_is_null_literal>::Compare(const char*, const char*, const T1&, const T2&) [with T1 = unsigned int; T2 = int; bool lhs_is_null_literal = false]’
test/objectstore/store_test.cc:411:5:   required from here
../src/gmock/gtest/include/gtest/gtest.h:1448:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (expected == actual) {
                ^
../src/gmock/gtest/include/gtest/gtest.h: In instantiation of ‘testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = int; T2 = unsigned int]’:
../src/gmock/gtest/include/gtest/gtest.h:1484:23:   required from ‘static testing::AssertionResult testing::internal::EqHelper<lhs_is_null_literal>::Compare(const char*, const char*, const T1&, const T2&) [with T1 = int; T2 = unsigned int; bool lhs_is_null_literal = false]’
test/objectstore/store_test.cc:2003:7:   required from here
../src/gmock/gtest/include/gtest/gtest.h:1448:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
../src/gmock/gtest/include/gtest/gtest.h: In instantiation of ‘testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = int; T2 = long unsigned int]’:
../src/gmock/gtest/include/gtest/gtest.h:1484:23:   required from ‘static testing::AssertionResult testing::internal::EqHelper<lhs_is_null_literal>::Compare(const char*, const char*, const T1&, const T2&) [with T1 = int; T2 = long unsigned int; bool lhs_is_null_literal = false]’
test/objectstore/store_test.cc:2010:7:   required from here
../src/gmock/gtest/include/gtest/gtest.h:1448:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
../src/gmock/gtest/include/gtest/gtest.h: In instantiation of ‘testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = long unsigned int; T2 = int]’:
../src/gmock/gtest/include/gtest/gtest.h:1484:23:   required from ‘static testing::AssertionResult testing::internal::EqHelper<lhs_is_null_literal>::Compare(const char*, const char*, const T1&, const T2&) [with T1 = long unsigned int; T2 = int; bool lhs_is_null_literal = false]’
test/objectstore/store_test.cc:2080:5:   required from here
../src/gmock/gtest/include/gtest/gtest.h:1448:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Signed-off-by: Sage Weil <sage@redhat.com>