Disable maintainer mode to make sure version.texi is always built
see https://github.com/baszoetekouw/pinfo/commit/8bcfa48ff71316501feec3ce8f61f51c3db8d71c
--- a/configure.ac
+++ b/configure.ac
@@ -43,8 +43,6 @@
 
 # init automake
 AM_INIT_AUTOMAKE
-# enable automatic rebuilding of ./configure, Makefile.in, and generation of # version.texi
-AM_MAINTAINER_MODE([enable])
 # include the m4 stuff in tools/macros
 AM_ACLOCAL_INCLUDE(macros)
 
