Add another header to Makefile
diff --git a/src/Makefile.am b/src/Makefile.am
index 9121a17..ddf1e85 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -100,6 +100,7 @@
   google/protobuf/generated_enum_util.h                          \
   google/protobuf/generated_message_reflection.h                 \
   google/protobuf/generated_message_table_driven.h               \
+  google/protobuf/generated_message_tctable_decl.h               \
   google/protobuf/generated_message_tctable_impl.h               \
   google/protobuf/generated_message_util.h                       \
   google/protobuf/has_bits.h                                     \