Make sure all files under the new shared dir are included in make dist.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13868 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/shared/Makefile.am b/shared/Makefile.am
new file mode 100644
index 0000000..df3a4ac
--- /dev/null
+++ b/shared/Makefile.am
@@ -0,0 +1,3 @@
+# We need to list all source files here to make sure they are included in
+# the make dist target.
+EXTRA_DIST = vg_replace_strmem.c