Link librt on the host when using sanitizers.

The sanitizers now use shared memory.

Change-Id: Ie8fa6690374eda08ee4138b68fd628ebbfa2d0c8
diff --git a/core/config_sanitizers.mk b/core/config_sanitizers.mk
index 41956cb..78cedad 100644
--- a/core/config_sanitizers.mk
+++ b/core/config_sanitizers.mk
@@ -82,7 +82,7 @@
   ifdef LOCAL_IS_HOST_MODULE
     my_cflags += -fno-sanitize-recover=all
     my_ldflags += -fsanitize=$(fsanitize_arg)
-    my_ldlibs += -ldl
+    my_ldlibs += -lrt -ldl
   else
     my_cflags += -fsanitize-undefined-trap-on-error
     my_cflags += -ftrap-function=abort