Add -lintl since it's not default in musl.

Upstream: not yet.

diff --git a/Source/WebKit/CMakeLists.txt b/Source/WebKit/CMakeLists.txt
index 6016921..9e92f1d 100644
--- a/Source/WebKit/CMakeLists.txt
+++ b/Source/WebKit/CMakeLists.txt
@@ -685,6 +685,8 @@ if (ATOMICS_REQUIRE_LIBATOMIC)
     list(APPEND WebKit_PRIVATE_LIBRARIES atomic)
 endif ()
 
+list(APPEND WebKit_PRIVATE_LIBRARIES intl)
+
 macro(ADD_WEBKIT_PREFIX_HEADER _target)
     if (WebKit_USE_PREFIX_HEADER)
         get_target_property(OLD_COMPILE_FLAGS ${_target} COMPILE_FLAGS)