fix build of neomutt-syntax.vim

diff --git a/doc/Makefile.am b/doc/Makefile.am
index a82eaa9f11184a2269e2785b5a7429a3dff40808..9a7afe3aaf009a99bbfc89a12c9b1cc5711f74e5 100644 (file)
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -157,7 +157,7 @@ manual.tex: stamp-doc-xml
        fi
 
 neomutt-syntax.vim: $(SAMPLE_VIMRC)
-       cat mutt-1.7.0-syntax.vim $^ > $@
+       cat $(srcdir)/mutt-1.7.0-syntax.vim $^ > $@
 
 validate: stamp-doc-xml
        xmllint --noout --noblanks --postvalid manual.xml