Don't delete in-tree m4 macros when doing maintainer-clean
-rw-r--r-- 48 AUTHORS
-rw-r--r-- 26527 COPYING
-rw-r--r-- 54 MAINTAINERS
-rw-r--r-- 1836 Makefile.am
-rw-r--r-- 12621 NEWS
-rw-r--r-- 511 README
-rwxr-xr-x 769 autogen.sh
drwxr-xr-x - backends
-rw-r--r-- 12082 configure.ac
drwxr-xr-x - docs
-rw-r--r-- 1061 folks.doap
drwxr-xr-x - folks
-rw-r--r-- 5464 git.mk
drwxr-xr-x - m4
drwxr-xr-x - po
drwxr-xr-x - tests
drwxr-xr-x - tools