[fs] fix build on OS X

Added kudu_fs dependency for kudu_fs_test_util library.

Prior to this patch, the following error was reported if trying to build
on OS X:

Undefined symbols for architecture x86_64:
  "kudu::fs::LogBlockManager::kContainerDataFileSuffix", referenced from:
      kudu::fs::LBMCorruptor::Init() in log_block_manager-test-util.cc.o
      kudu::fs::LBMCorruptor::CreateIncompleteContainer()
          in log_block_manager-test-util.cc.o
  "kudu::fs::LogBlockManager::kContainerMetadataFileSuffix", referenced from:
      kudu::fs::LBMCorruptor::Init() in log_block_manager-test-util.cc.o
      kudu::fs::LBMCorruptor::CreateIncompleteContainer()
          in log_block_manager-test-util.cc.o
  "fLU64::FLAGS_log_container_max_size", referenced from:
      kudu::fs::LBMCorruptor::Init() in log_block_manager-test-util.cc.o
  "kudu::BlockId::CopyToPB(kudu::BlockIdPB*) const", referenced from:
      kudu::fs::LBMCorruptor::AddMalformedRecordToContainer()
          in log_block_manager-test-util.cc.o
      kudu::fs::LBMCorruptor::AddMisalignedBlockToContainer()
          in log_block_manager-test-util.cc.o
      kudu::fs::LBMCorruptor::AddPartialRecordToContainer()
          in log_block_manager-test-util.cc.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [lib/libkudu_fs_test_util.dylib] Error 1

Change-Id: I60e16871818bb8994a2ecc59628ba22633ece3ba
Reviewed-on: http://gerrit.cloudera.org:8080/6756
Reviewed-by: Adar Dembo <[email protected]>
Tested-by: Alexey Serbin <[email protected]>

src/kudu/fs/CMakeLists.txt

@@ -46,6 +46,7 @@ add_library(kudu_fs_test_util
 
 target_link_libraries(kudu_fs_test_util
   fs_proto
+  kudu_fs
   kudu_util
   gutil)