Fix out-of-tree builds.

git-svn-id: https://znc.svn.sourceforge.net/svnroot/znc/trunk@2223 726aef4b-f618-498e-8847-2d620e286838

modules/Makefile.in

@@ -61,9 +61,9 @@ ifeq "@EXTRA@" "yes"
 FILES    += $(addprefix extra/, $(notdir $(wildcard $(srcdir)/extra/*.cpp)))
 endif
 
-include modperl/Makefile.inc
-include modpython/Makefile.inc
-include Makefile.modtcl
+include $(srcdir)/modperl/Makefile.inc
+include $(srcdir)/modpython/Makefile.inc
+include $(srcdir)/Makefile.modtcl
 
 FILES    := $(basename $(FILES))