Add missing header file.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15108 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/Makefile.vex.am b/Makefile.vex.am
index 09a8db6..8e1ec3c 100644
--- a/Makefile.vex.am
+++ b/Makefile.vex.am
@@ -57,6 +57,7 @@
 	priv/host_arm_defs.h \
 	priv/host_arm64_defs.h \
 	priv/host_s390_defs.h \
+	priv/host_tilegx_defs.h \
 	priv/s390_disasm.h \
 	priv/s390_defs.h \
 	priv/host_mips_defs.h \