Add an extra install target.

Added an extra make target named install-regression that does the same a
a normal make install but doesn't do the specific platform install. On
a regression install it makes little sense to install platform files
like init scripts etc.

Makefile.in

@@ -118,6 +118,9 @@ install: installdirs
 	@for I in $(all_subdirs); do (cd $$I && $(MAKE) DESTDIR=$(DESTDIR) $@ || exit 1); done
 	(cd platforms && $(MAKE) DESTDIR=$(DESTDIR) $@ || exit 1)
 
+install-regression: installdirs
+	@for I in $(all_subdirs); do (cd $$I && $(MAKE) DESTDIR=$(DESTDIR) $@ || exit 1); done
+
 install-autostart:
 	(cd platforms && $(MAKE) DESTDIR=$(DESTDIR) $@ || exit 1)