configure.ac: Depend on osmo-release.mk

The osmo-release.mk script can be found in libosmocore and it is used in
most osmocom related projects to help create new releases.

LIBVERSION is moved to src/Makefile.am since osmo-release.mk greps for
Makefile.am to find LIBVERSIOn changes. In any case, we don't need in
the global include makefile.

Change-Id: I5d163535c34369c74ece26574c8b1601bc1697b7
diff --git a/Makefile.am b/Makefile.am
index deb3299..1fabe69 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,7 @@
 include $(top_srcdir)/Make_global.am
 
+@RELMAKE@
+
 ACLOCAL_AMFLAGS = -I m4
 
 SUBDIRS = src include tools