[administrivia] Add .gitignore files, based on .cvsignores.
diff --git a/m4/.gitignore b/m4/.gitignore
new file mode 100644
index 0000000..2f02fdb
--- /dev/null
+++ b/m4/.gitignore
@@ -0,0 +1,4 @@
+Makefile
+Makefile.in
+.arch-inventory
+.arch-ids