Fix win_sdk build.

libutils has been moved to system/core/libs/utils.

Change-Id: Ifd75fd7d5bac8aa24be876860eba030c3b5ae3fb
diff --git a/build/windows_sdk_whitelist.mk b/build/windows_sdk_whitelist.mk
index 4ef2aec..b9f7196 100644
--- a/build/windows_sdk_whitelist.mk
+++ b/build/windows_sdk_whitelist.mk
@@ -53,6 +53,7 @@
 	system/core/liblog \
 	system/core/libsparse \
 	system/core/libzipfile \
+	system/core/libs/utils \
 	system/extras/ext4_utils
 
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