Fix -DBUILD_SHARED_LIBS=on build after r362977

The executable has an undefined reference to lld::Saver, the library
should be explicitly linked.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@363023 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/lld/CMakeLists.txt b/tools/lld/CMakeLists.txt
index d882949..a15e296 100644
--- a/tools/lld/CMakeLists.txt
+++ b/tools/lld/CMakeLists.txt
@@ -8,6 +8,7 @@
 
 target_link_libraries(lld
   PRIVATE
+  lldCommon
   lldCOFF
   lldDriver
   lldELF